Double Chocolate Mousse Cake
Ever wondered what eating chocolate air is light? If biting into the lightest and fluffiest chocolate mousse cake is something you’ve always wanted to experience, then this double chocolate mousse cake recipe is just for you!
My perfectly light double chocolate mousse cake starts off with a chocolate brownie base that is topped with the lightest and most splendid mousse you’ve ever had. Slicing into this cake is so satisfying, eating it is simply divine!
Table of Contents
My favorite thing…
My favorite thing about this Double Chocolate Mousse cake? The Mousse! It’s so light and airy! You can’t see it in the video but it felt so satisfying slicing through it. The trick is to warm up your knife first which gives you nice clean slices!
What does the mousse cake taste like?
Well, chocolate, right? Duh Nick? But let’s talk about the texture. The texture of the brownie base is fudgy. It’s really chocolatey too. The mousse is really light, it’s very creamy and not too sweet.
What happens if I don’t have gelatine leaves?
Well, you can use powdered gelatin. This recipe calls for 2 gelatin leaves. If using powder, you’ll need 2 tsp. To prepare the gelatine powder, simply add to a mixing bowl with 3 tsp of water and stir using a fork. Set aside to bloom (soak in the water) for 5 minutes then add to the hot milk and stir until melted.
What you need for the Double Chocolate Mousse Cake
Brownie Base
Unsalted butter – I used unsalted here. But you may use salted if you want some salt in the recipe. It will help break the sweetness a little.
Dark chocolate – I used nestle cooking melts.
Brown sugar – you can use caster sugar in it’s place if you wish. The brown sugar adds a richer flavor.
Eggs – I used large eggs
All-purpose flour – regular all purpose flour.
Mousse
Milk and dark cooking chocolate – a combination of both helps make this a smooth chocolate flavor. For a less sweet and more intense chocolate flavor, replace the milk chocolate with dark chocolate.
Gelatin leaves – see my notes above on this. But I used gelatin leaves for this recipe because it’s preferable. But you can use powdered gelatin if you wish.
Heavy whipping cream – Use cream with at least 30% fat content. This is the cream you use for whipping.
Caster sugar – This sugar is best for this recipe because it will dissolve in the meringue much quicker than granulated sugar.
How to make the mousse cake
Brownie Base
1. Fill a pot a quarter of the way with water and bring to a gentle boil.
2. Add the butter, chocolate, and brown sugar
3. Stir until melted.
4. Take off the heat and add the eggs. Whisk to combine.
5. Add the flour and whisk until the batter is smooth.
6. Add to a springform pan lined with baking paper and bake for 20 minutes on 180°C / 350°F.
7. Once baked and cooled, carefully run a knife around the sides of the brownie to loosen.
8. Take out of the pan. Spray the side with oil spray.
9. Add acetate measuring 65cm (26-inches) in length on the inside.
10. Add the brownie back in the pan and set aside.
Mousse
1. Add the milk and dark chocolate to a heatproof bowl over a double boiler. Stir until melted and smooth.
2. Take off the heat and add the 6 egg yolks. Stir using a spatula until well combined. Set aside
3. Add the gelatin leaves to a bowl of cold water. Allow to soak for 5 minutes.
4. Take out and squeeze out excess water.
5. Transfer to a jug of hot cream (1 cup – 250ml) and stir until melted.
6. Add the hot gelatin cream to the chocolate mixture and stir until thinned out and smooth. Set aside.
7. Add the remaining 2 1/2 cups – 625ml of cream to a mixing bowl with the vanilla extract and whip to stiff peaks.
8. Add the 6 egg whites to a separate large bowl that is very clean. With clean beaters, whip to soft peaks.
9. Slowly add the sugar while mixing on high speed. Once all the sugar is in there continue mixing for 2 minutes until thick and glossy.
10. Add the cream to the chocolate mixture and use a spatula to fold through.
11. Add the meringue to the chocolate mixture and gently fold through with the spatula.
12. Pour the mousse mixture to the prepared springform pan.
13. Use a spatula to flatten out the top and chill in the fridge for 4 hours or overnight.
Let’s unwrap this thing!
Let’s Decorate!
1. Firstly, run a hot and dry knife around the top of the mousse cake.
2. Unclip the springform pan and take away the sides.
3. Use a warm cloth to run around the mouse section of the cake to help the mousse come away from the acetate easier.
4. Gently unwrap the mousse cake from the acetate and transfer to a serving plate. Slice using a warm knife to serve.
Tips for making Double Chocolate Mousse Cake
- When slicing through the mousse cake, warm up your knife first by running it under hot water and drying it with a towel. It’ll give you those really clean straight slices that elevates the presentation of this cake!
- Use a warm cloth to wipe the side of the set mousse cake before unwrapping. This will help the mousse come away from the acetate without tearing.
Other Recipes You Might Like!
Chocolate Cake
Chocolate Ganache Frosting
Greek Frape Cupcakes
Candy Apple Cupcakes
Flourless Chocolate Cake
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I hope you guys enjoyed this simple but delicious recipe with me. Please comment in the comments section below, or feel free to share with your family and friends on social media. I’ll see you all on the following recipe. Happy baking!
N x

Double Chocolate Mousse Cake
Serves 12
Ingredients
Brownie Base
- 1/2 cup (130 g) unsalted butter (+ 1 tbsp of butter)
- 3/4 cup (160 g) dark cooking chocolate
- 3/4 cup (150 g) brown sugar
- 2 egss
- 1/3 cup (50 g) all-purpose flour
Mousse
- 2 cups (400 g) milk cooking chocolate
- 2 cups (400 g) dark cooking chocolate
- 6 eggs
- 2 gelatine leaves
- 3 1/2 cups (900 ml) heavy cream
- 1 tsp vanilla extract
- 1/2 cup (110 g) caster sugar
Learn How To Make it! [VIDEO]
Instructions
Brownie Base
- Preheat your oven to 180°C / 350°F. Spray an 8-inch springform pan with oil spray and line the bottom with baking paper.
- Fill a pot about a quarter of the way with water. Bring to a gentle boil. Place a heatproof bowl on top and add the butter, chocolate, and brown sugar. Stir until all the ingredients have melted. Take off the heat and add the eggs, whisk to combine. Add the flour and whisk until the batter is smooth.
- Add to the springform pan and bake for 20 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.
- 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
- Add the milk and dark chocolate in a heatproof bowl over a double boiler. Stir until melted.
- Take off the heat and add the egg yolks. Mix using a spatula. The mixture will instantly thicken and become almost dough like. Set aside.
- Add gelatine leaves to cold water to soak for 5 minutes. Take out and squeeze out excess water. Place in a jug with 1 cup of the cream which has been heated. Stir until gelatine is melted.
- Add the hot cream to the chocolate egg mixture and stir until smooth. Set aside.
- Add the egg whites to a separate large bowl. Make sure the bowl is clean. Use an electric hand mixer to whip to soft peaks. Add a third of the sugar and whip for one minute. Repeat until all the sugar is in. Once in, whisk on high speed for 2 minutes until meringue is thick and glossy.
- Finally, to a separate bowl whisk the remaining cream and vanilla extract together until you reach stiff peaks.
- Add the cream to the chocolate module and gently fold through until well combine. Add the meringue and fold through until well combined.
- Pour the mixture into the prepared springform pan. Use a spatula to flatten out the top. Chill in the fridge for four hours or overnight.
- To remove, 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.
38 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? 🙂
That would be ok 🙂 N x
Hi Nick, could you use this mouse as a filling for between cake layers?? Sounds amazing 🥰
Hi Monique! Sorry about the late reply. For this recipe, it wouldn’t be stable enough to hold the weight. Nx
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 🙂 N x
Since we are not cooking the eggs, isn’t 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 they’re not.. I don’t 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 don’t need gelatin you can use agar agar powder you don’t 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 don’t need eggs or egg whites you can use aquafaba you don’t need egg yolks either in any recipe for that matter! None any of those animal derived ingredients is needed. I’m 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 that’s plant-based so people can eat it and not get sick? It’s really sad when you can avoid animal cruelty to make a really yummy recipe but it’s not avoided. I’ll 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!
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. 🙂
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 🙂
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 I’m 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