Chocolate Brownie Mousse Cake
Each slice of this Chocolate Brownie Mousse Cake is absolute heaven! Itโs a two layered cake that starts with a rich and decadent brownie. Then you have a high, lighter than air chocolate mousse that melts in your mouth.
This cake isnโt for the faint of heart, itโs decadent! My perfectly light double chocolate mousse cake starts off with a chocolate brownie base that is topped with the lightest and most splendid mousse youโve ever had. Slicing into this cake is so satisfying, eating it is simply divine!
Every wondered what eating chocolate air is like? This mousse is the answer! Itโs got eggs that are perfectly whipped, paired with whipped cream and chocolate, it all comes together to create a lighter than air mousse. Itโs not as airy as most other mouses, but itโs rich, perfectly set and each slice melts in your mouth.
If youโre as obsessed with chocolate desserts as I am, I have loads of recipes on the blog but my top recommendations are my Classic Chocolate Mousse, Fudgy Chocolate Brownie Pie and my Easy Chocolate Fudge Cake. All great chocolate desserts. Iโll leave a longer list at the bottom of this post!
Dreamy Chocolate Mousse in Cake Form!
I love this multi layered chocolate cake because it combines two of my favorite things. Creamy Mousse on top of a deliciously rich and fudgy brownie layer. Hereโs some reasons youโll love it!
- Light and smooth – although not as airy as most other mousse cakes, the mousse layer is ultra light and silky in every bite!
- Fudgy Brownie Layer – rich, buttery and chewy. Such a great contrast in texture to the mousse.
- Ultra-chocolate hit – this recipe uses cocoa powder and melted chocolate with a little hint of coffee to intensify the rich chocolate flavor found throughout the dessert.
Why this recipe works
A combination of gelatin and chocolate helps set this cake. Itโs what helps give the mousse enough structure to stand on itโs own. The whipped eggs (gently cooked and safe to eat) combined with the whipped cream help make it light and airy!
Ingredients You Need To Make Double Chocolate Mousse Cake
Note: the whole recipe, including the ingredient quantities, can be found at the bottom of this page โ just scroll down to the bottom, or click the โJump to Recipeโ button at the top of this post.
Brownie Layer
- Butter – I used unsalted butter.
- Cooking chocolate – make sure you use dark cooking chocolate. This can be found in the baking isle.
- All-purpose flour – also known as plain flour.
- Cocoa powder – use Dutch processed if you can because it has a stronger chocolate flavor and is less acidic. Natural will also work.
- Salt – I used fine salt.
- Eggs – I used large eggs.
- Caster sugar – also known as superfine sugar. Granulated sugar will also work.
- Brown sugar – light or dark will work.
- Vanilla Extract – Always use good quality vanilla extract when baking, it makes a huge difference. I have a great recipe here for it if youโd like to try your own!
- Coffee shot – You can use a coffee machine to do this or just combine 2 tsp instant coffee powder with 1 tbsp boiling water.
Chocolate Mousse Layer
- Cooking Chocolate – I used dark cooking chocolate. Specifically, the Nestle cooking buttons which are designed to be easily melted and used for baking and desserts. They can be found in the baking isle of your supermarket.
- Eggs – I used large eggs. For this recipe youโll need to separate your eggs. Itโs easier to separate your eggs if theyโre cold. Iโve updated the recipe method to gently cook the eggs which makes them safe to eat.
- Gelatin leaves – the gelatin leaves help the mousse set. There are different types of gelatin and different strengths. I used gelatin leaves which need to be soaked in water before being added to something warm to melt. In this case, the warm ganache for the mousse mixture. Strength wise: youโll need a platinum strength gelatin. You can use gelatin powder instead. Simply mix 3 tbsp of gelatin powder with 6 tbsp cold water. Mix using a fork and allow to rest for 5 minutes. This is what youโll add to your chocolate mixture and stir through until completely melted.
- Vanilla Extract – same as above.
- Caster sugar – also known as superfine sugar. Caster sugar is ideal for the mousse portion of the recipe as it melts into the meringue more easily than granulated sugar, reducing the risk of overwhipping and getting grainy mousse.
How to make Double Chocolate Mousse Cake!
For the full steps, check out the recipe card at the bottom of this post.
Brownie layer
- Melt the butter and chocolate over a double boiler.
- Combine the dry ingredients together.
- Whip the eggs and sugar together.
- Add the coffee shot (optional)
- Mix in the cooled chocolate and butter mixture.
- Add the dry ingredients and fold through.
- Pour into a greased and lined springform pan and bake.
Mousse Layer
- Once baked, allow the brownie layer to cool completely, take out of the springform pan and line the side of the pan with acetate. More on acetate and where to buy it below.
- Soak the gelatin leaves (more on what to use instead of leaves below!)
- Melt the chocolate over a double boiler
- Mix soaked gelatin into the warm chocolate. Add the egg yolks and mix. Allow to cool.
- In a separate bowl, mix the egg whites and sugar and then stir over a double boiler until the sugar is melted.
- Allow to cool slightly before whipping until thick and glossy.
- Whip the heavy cream until you reach stiff peaks.
- Fold the meringue through the cooled (very slightly warm is ok) chocolate mixture and then fold through the cream.
- Add to the prepared tin.
- Allow to set in the fridge for 4 hours, ideally overnight before unclasping and peeling acetate away.
What happens if I donโt have Gelatin leaves?
Gelatin is one of the key things that helps this mousse set. If you donโt have them in leaf form, use gelatin powder. To use gelatin powder, simply mix 3 tsp of gelatin powder with 3 tbsp cold water. Mix using a fork and allow to rest for 5 minutes. This is what youโll add to your chocolate mixture and stir through until completely melted.
What if I donโt have acetate?
I used acetate to help make taking this cake out of the springform pan easier. I bought mine on Amazon. If you search for food grade acetate it will come up. Anything about 4 inches in height is ideal. If you donโt have acetate, you can make this without it! Simply pour the mousse into the springform pan, let it set and then before unclasping it, dip a towel in hot water. Wrap the towel around the springform pan and allow it to warm the sides of the pan for 60 seconds. This will gently melt the mousse against the cake pan and help it slide out instead of sticking to the cake pan.
Tips and Tricks For Recipe Success!
- Measure out using kitchen scales – measuring ingredients out by weight and not cups is the best way to get consistent results every time!
- Make sure the chocolate is warm when adding the gelatin but cooled before adding the whipped ingredients. Donโt skip any of the steps!
- Donโt skip any of the whipping! Whipping the egg whites and heavy cream are super important to helping this mousse get its air bubbles and light texture.
- For a flawless slice – Before slicing into your cake, warm your knife up under some hot running water and then dry it. Do this with every slice for a restaurant quality flawless slice!
- Itโs really important that you allow adequate time to let this mousse set. I like letting it set overnight but you can give it a good 4-5 hours in a cold fridge before unclasping.
Frequently Asked Questions about This Mousse Cake!
How do I store this?
This mousse cake can be made up to 2-3 days in advance. Simply store in an airtight container in the fridge. This cake can not be frozen.
Can this recipe be made gluten free?
Yes! There is flour in the brownies. You can replace the all-purpose flour (plain flour) with gluten free flour.
Can I leave the chocolate out?
Yes! The chocolate is in the brownie layer to help intensify the chocolate flavor but can be left out completely.
What is the best chocolate to use in the mousse layer?
Dark cooking chocolate. Itโs designed to be easily melted and use in baking recipes. It can be found in the baking isle of your supermarket.
Gave this a go? Donโt forget to rate the recipe and leave a comment below! Hungry for more? Join me on Instagram, Facebook, Pinterest and TikTok for more great recipes!
If you loved this recipe, check these out!
Chocolate Cheesecake
Classic Chocolate Mousse
Easy Chocolate Cake
Chocolate Eclairs
Chocolate Pastry Cream
Fudgy Chocolate Brownie Pie
Easy Chocolate Fudge Cake
Did you make this? Be sure to leave a review below and tag me @thescranline on Facebook and Instagram!
Chocolate Brownie Mousse Cake
Serves 8
Ingredients
Brownie Layer
- 83 g unsalted butter, cut into cubes
- 100 g dark cooking chocolate, see notes
- 75 g all-purpose flour, plain flour
- 16 g Dutch process cocoa powder, sifted (see notes)
- Pinch of salt
- 2 large eggs, 55g each, room temperature
- 70 g caster sugar, superfine
- 65 g brown sugar
- 7 g vanilla extract
- 1 coffee shot, 20ml (see notes)
Chocolate Mousse Layer
- 735 g dark cooking chocolate
- 3 large eggs, 55g each, separated
- 3 gelatin leaves, platinum strength or above (see notes)
- 185 g heavy cream, for chocolate mixture (see notes)
- 250 g heavy cream, cold, for whipping
- 7 g vanilla extract
- 55 g caster sugar
Learn How To Make it! [VIDEO]
Instructions
Brownie Layer
- Preheat a fan forced oven to 160C/320F (180C/355F for no fan). Spray and line the bottom of an 20cm / 8-inch springform pan. Set aside.
- Melt chocolate – Add the butter and chocolate to a heatproof bowl and microwave for 30 seconds at a time, stirring each time until melted. Alternatively, you can do this using a double boiler. Set aside to cool slightly.
- Combine dry ingredients – Add the flour, cocoa powder and salt to a small mixing bowl and use a whisk to combine.
- Whip eggs and sugar – To a large mixing bowl, add the eggs, both sugars and vanilla extract. Use an electric hand mixer to whisk until pale, fluffy and doubled in volume, about 2-3 minutes.
- Add coffee and chocolate – Add the coffee shot and mix until combined. Next, add the cooled chocolate mixture and whisk until well combined. Use a spatula to scrape the bowl down.
- Add dry ingredients – Add the dry ingredients and fold using the spatula until no dry ingredients are showing.
- Bake – Add the mixture to the springform pan and bake for 15 minutes. Once baked, allow to cool completely at room temperature. Carefully run a knife around the edge of the brownie to loosen from the springform pan. Clean the inside of the springform pan. Place a piece of baking paper on bottom and place the sides on top. Clip to tighten.
- Add acetate – Spray the side of the pan with oil spray and place a large piece of acetate measuring 65cm (26-inches) in length on the inside. The oil will help it stick to the pan. Place the cooled brownie in the pan and set aside.
Mousse Layer
- Melt chocolate – Add the dark chocolate and 3/4 cup (185g) heavy cream to a heatproof bowl over a double boiler. Stir until melted. Take off the heat and add the egg yolks, mix using a spatula until combined. Keep the double boiler set up on the stove.
- Prepare gelatin – Add the gelatin leaves to cold water and allow to soak for 5 minutes. Once bloomed, take out of the water and squeeze excess water out. Add to the chocolate mixture and stir until gelatin is melted. Set aside to cool slightly.
- Whip cream – Add the remaining 1 cup (250g) of heavy cream and 1 tsp of vanilla extract to a medium sized mixing bowl and whip using an electric hand mixer until you reach stiff peaks. Set aside in the fridge until ready to use.
- Make Swiss meringue – Add the egg whites and sugar to a large heatproof bowl and place on top of a double boiler (see notes for how to prepare double boiler). Whisk for 5 minutes or until the sugar has dissolved completely. You can test this by feeling it in between two fingers.
- Whip egg whites – Take off the heat and allow to cool for 10 minutes. Use an electric hand mixer to whip until the mixture doubles in size and becomes thick and glossy.
- To complete the mousse – Add half the meringue to the chocolate mixture and gently fold through using a spatula until well combined. Add the remaining meringue and the whipped cream and fold through until evenly combined.
- Chill mousse – Pour the mixture on top of the cooled brownie layer and spread around as evenly as you can. Chill in the fridge overnight or for a minimum of 6 hours. This needs a good amount of time to set properly.
- To remove from the pan – Run a knife under hot water and dry. Run it around the top of the mouse layer before loosening it from the springform pan. Carefully lift up the sides of the pan. Gently unwrap it from the acetate and slice to serve.
70 comments
Would it be ok to half the mousse recipe so it isn’t so tall, or would it affect the texture/setting of it? ๐
That would be ok ๐ N x
Hi Nick, could you use this mouse as a filling for between cake layers?? Sounds amazing ๐ฅฐ
Hi Monique! Sorry about the late reply. For this recipe, it wouldn’t be stable enough to hold the weight. Nx
What can i use instead of gelatin if possible ?
Hi Anna! Unfortunately, I’m not sure what would work in place for this recipe as I’ve only tested it with geltine! N x
I like to bake alot and tried your recipie tonight. Unfortunately I could not find my 8inch springform pan so had to use a 9 inch and so the brownie was a little more thin than your recipie but it is delicious …and I am very finicky with baking. Your mousse is so light and it is a desert one would buy in a restaurant. thank you for this recipie
That’s so lovely to hear Claire! I’m glad the recipe worked out and that you enjoyed it ๐ N x
Since we are not cooking the eggs, isnโt it like having raw eggs?
Hi Kirti! Yes. the eggs in this recipe are raw. In most countries (but not all) raw eggs are safe to eat. N x
No theyโre not.. I donโt know who told you this but raw eggs can make peoooe very ill and you never mention even buying pasteurized eggs not that it matters. This recipe is full of animal cruelty based ingredients literally from the gelatin to the egg whites the yolks the cream literally all animal cruelty all the way through! no reason for any of it you donโt need gelatin you can use agar agar powder you donโt even need that cream you can use coconut cream or that silk brand whipping cream you can use coconut cream you can use other cream alternatives you donโt need eggs or egg whites you can use aquafaba you donโt need egg yolks either in any recipe for that matter! None any of those animal derived ingredients is needed. Iโm not sure I understand why make a recipe with raw ingredients from an animal source that can make people sick when you can just swap it out for some thing thatโs plant-based so people can eat it and not get sick? Itโs really sad when you can avoid animal cruelty to make a really yummy recipe but itโs not avoided. Iโll never understand this way if thinking.
Bella, other people exist in this world that have different views than you about ingredients or access to different ingredients that are safe to eat raw. I’m not going to sit here and try to change your mind because you have made your point and views crystal clear.
How funny, I don’t remember saying this recipe was vegan?
Hi bella, this is a non vegan recipe. If you want a vegan chocolate mousse recipe you should’ve gone on a vegan blog instead. If using animal products is cruel to you why did you come onto this website/blog in the first place. And also, in the UK and in Europe and Asia also, we use raw eggs all the time when making no baked desserts and even have semi cooked eggs, the way the food industry handles our eggs is safe. We also keep our eggs outside of the fridge. No harm to millions and millions of people. Please educate yourself, don’t wash your eggs until you need to actually use them that is only if there is physical dirt on them like a feather or something, because if you wash your eggs way before you eat them they will go bad faster, wash your hands after handling eggs if it gets messy, there you go no harm done.
Don’t put this wonderful food blogger down with your negative post. Thank you.
Thankyou very much Jess. Very well written and 100% agree!
Can you use powdered gelatin if the leaves are unavailable? If so, what would the ration be?
Hey Lauren! Yes, you can use powdered gelatin if you donโt have leaves. Just use 3 teaspoons of powdered gelatin and mix it with 3 tablespoons of cold water. Let it bloom for 5 minutes, then add it to the chocolate mixture. N x
Hi Nick,
This recipe looks amazing! I’d like to use it as a second tier (much smaller, like 6-7in), I’m thinking to add another layer of brownie base between mousse. Do you think that would work? Would you let the mousse set in-between laying it?
Thank you! Xx
Hey Clara! Thanks for the love! I wouldnโt recommend adding another brownie layer because the mousse isnโt strong enough to hold it, and it would make slicing tricky. Maybe try a thicker brownie base instead. Hope that helps! N x
Nick I canโt find acetate can I use baking paper?
Hey Michelle! Yes, you can definitely use baking paper if you donโt have acetate. It won’t stick as well, but itโll still help release the mousse from the pan. Just make sure to spray the sides of the pan with oil so it stays in place. Hope that helps! N x
The thought of the gelatin is freaking me out – but this dessert looks sooo yummy! What does the gelatin add? Is it still super light and fluffy and not at all jelly-like? ๐
Hey Willow! The gelatin just helps the mousse set so it holds its shape, but donโt worry! Itโs still super light and fluffy, not jelly-like at all. Youโll love it! N x
Hi, Is there a specific type of gelatin sheet to use cause mine looks longer than yours?
Hmm, I used the McKenzies Gelatin sheets. 3 of those sheets are equal to 1 tsp of gelatin. Hope that helps! N x
Hello – I have a question regarding the amount of chocolate. For ‘2 cups’ – is the the equivalent of 16 ounces, or one pound? Thank you!
Hi Kate! Hmm, 2 cups of chocolate is equal to 400g. ๐
Hi (again) – I had asked about the ounce equivalent for the ‘2 cups of chocolate’; but – I now see that you have the handy metric tab to convert the recipe. Thank you for that!! (you can ignore my earlier question)
Thanks Kate! N x
Hi! When you say dark cooking chocolate do your mean unsweetened baking chocolate?
Hi Tara! That’s right! N x
I halved the recipe and made them in cupcake liners. My first time making mousse. Love it, thank you ๐
That’s amazing Deanne! Glad you loved the recipe! Nx
Hi Nick! Can you help me adapt this recipe to make it a dark chocolate mousse cake? My family likes dark chocolate. I could add coffee or rhum to intensify the flavor, but I certainly need to make changes to the type of chocolate used and the quantity of sugar. How would you adapt it to make it a dark chocolate mousse cake?
I would swap the semi-sweet chocolate for 70% cooking chocolate. It’ll have a more dark/bitter flavour. I would not recommend making changes to the quantities of any of the ingredients N x
In step 2, do you add the ingredients in to the water? How much water?
Nope, you add them into the bowl. N x
If you don’t have acetate what can you use instead?.
Hi Tamara, Hmm, I got this question yesterday. Unfortunately for this recipe, there isn’t an alternative. Sorry! N x
Your recipe looks amazing and Iโm super excited to try it out but I cannot seem to find acetate anywhere? What is a good alternative for this? Cling wrap? Baking paper?
Hi Carolina! I bought mine on amazon. Unfortunately, for this recipe I’m not sure there is an alternative. Acetate keeps it’s shape and doesn’t wrinkle.
How many grams in a cup of chocolate in your recipe?
In each cup of chocolate I get 200g chopped chocolate or chocolate chips.
This cake really was heaven on a spoon
Just wondering how long in advance could I possibly make this
Hmm, I’d say no more than 2 days. Hope that helps! N x
If you love chocolate you will love this but it is sooooooo rich. I never thought I would write that about chocolate. We won’t be eating any more only because it is way too rich for us. It was an easy recipe to make though and it turned out beautiful.
Thanks so much Kathryn! N x
I havenโt made this yet so rating it would be daft, but doesnโt it look and sound fabulous! My question is: would this freeze well in a silicone cake mould to later cover in velvet lustre or mirror glaze – specifically the mousse?
Hmm, I don’t think it would actually. Might be too soft to carry the weight of the glaze.
Hi I donโt have leave gelatine
Please can you advise me on
I do have powder gelatine
How much do I need to use for this recipe
And how much water
Weโve tried loads of receipes but none of them are light
Also being a Muslim we canโt eat the ones from the shops
I canโt wait to get started and make the most amazing chocolate mousse cake
I will give you the feedback
Off to the shops to do the shopping
Thank you in advance for the receipe
Hi Amina! I understand and appreciate you can’t have gelatin. Totally get that. Unfortunately I haven’t tested this recipe using alternatives, so I couldn’t tell you how to make it using alternatives. However, if you do find a way to make it without gelatin and are happy with the results, please let me know and I’ll add a note to the blog post for anyone else who may be similar to you in their eating preference/beliefs. Nick xo
The cake is very, very decadent and sweet; a lil too sweet for my taste but perfect for anyone who loves that sort of thing, My mom definitely does and she requested something soft and creamy, so I found this recipe and made the cake for her birthday today. She absolutely loved it and so did all the guests.
P.s. for those wondering, I used gelatin powder (2tsp and 3tsp of water as instructed) and it turned out perfect.
Thanks Jovy! N x
Hi Nick, Iโm a little confused in the mousse instructions before the actual recipe it mentions 6 eggs but in the recipe it says 3 which is correct please. Cheers Lesley
Hey Lesley! Sorry for the confusion. Itโs 3 eggs for the mousse, and Iโve updated the recipe to reflect that. Thanks for pointing it out! N x
Just made the mousse with a pate sablee type crust, not the brownie so I am only rating that. I used powder gelatin. It took a bunch of whisking not just folding to get the chocolate/gelatin/cream mixture smooth, as the gelatin had already stiffened the chocolate a little. I’m not very experienced with gelatin so it could be user error, nevertheless the finished product was wonderful. The texture was perfect.
Thank you for a lovely recipe and I will make it again.
Thank you for the recipe.
Thanks Nico ๐
Where is the metric tab you mentioned? I don’t see it!
Hi maria, I can’t see any mention of a metric tab in this post. I used to have one, but I took it away as i have started switching my recipes to all grams. For the recipes that havent been converted yet I have both grams and cups already listed ๐ Hope that helps! N x
Hi Nick, I’m a newbie to upscale baking and made this recipe. I didn’t know that different gelatin leaves have different streangths since it wasn’t noted on the packaging … my dessert was firm, but still awesome – the mousse was dreamy when I tasted it as I added it, the brownie layer was amazing and in the final, although it was much firmer than intended, melted very quickly while enjoying – not rubbery. Will try again with 1/2 the leaves called for. SO worth it!
Also, for the record, I’m from the US. I’ve been eating raw eggs in cookie dough and raw batter all of my life. I’ve never been sick or known anyone to get sick from raw eggs. It wasn’t worth the hassel of pasturizing my own eggs – took two tries and gave up, so raw it is!
Thanks for sharing your recipes and tips!
Hey Suzanne! Thanks so much for giving this recipe a goโit sounds like you did an amazing job even with the firmer mousse! Gelatin strengths can definitely be tricky when the packaging isnโt clear, but halving the leaves next time sounds like a great plan. Iโm so glad you loved the brownie layer and the dreamy mousse flavor!
As for the raw eggs, I hear youโlots of people stick with them, and itโs awesome that youโve found what works for you. I just suggest the extra step for anyone whoโs cautious, but youโre clearly a pro at making it work. Thanks for the lovely comment and for sharing your experience. Canโt wait to hear how your next try goes! N x
Hi Nick – is it possible to freeze this?
Hi Jess! I don’t think so. I havent tried freezing it to know for sure but I suspect it would melt into a puddle if it was defrosted.
When do you add the butter to the brownie mix? It’s not in the method. Thanks
Hey AJ! So sorry about thatโthe butter is melted with the chocolate. Iโve updated the recipe to make that clear now. Thanks for catching it, and I hope you enjoy the brownies! N x
Hi Nick,
Gonna try your recipe for the holiday. For baking the brownies base, I assume the butter is going to be melted together with th choc using double boiler or microwave?
Hey Beth! Thatโs rightโyouโll melt the butter and chocolate together, either in the microwave or over a double boiler. It helps create that rich, fudgy texture for the brownie base. Enjoy making it for the holiday! N x
You might consider updating the actual recipe section at the bottom… it doesn’t mention the butter addition, aside from it being in the ingredients. I’ve had my brownie mix in the oven for 10min and just realized I never added it because I was following the succint directions versus the step by step more at the top of this page (hope that makes sense!). Hoping I have enough ingredients to stat again…
Hey Kelli! Iโm so sorry about that and Iโve updated the recipe now to include the butter in the instructions. Thanks so much for letting me knowโitโs super helpful, and I hope you were able to make it work! N x