Swiss Meringue Buttercream Frosting

Frosting

• Before you begin, it’s really important to make sure the butter is soft enough. Some people keep their butter out of the fridge, others chill it. Even if you keep it out, it may not be soft enough. You want your butter to be soft enough so that when you stick your finger in it, it glides in, but not without a little bit of resistance. The best way to get it too that softness is to place your butter on a microwave safe plate, microwave for 10 seconds at a time, testing the softness each time. If it needs longer than 10 seconds, turn the butter over and repeat until it’s ready.
• Fill a large saucepan one-quarter of the way with water. Let it come to a gentle boil over a medium–high heat.
• Separate your egg whites from your yolks in a large, very clean, glass or metal mixing bowl. We only need the egg whites for this recipe, so you can store the yolks in an airtight container in the fridge to use for something else. If you need ideas, there are loads on the internet, but my go-to recipe for using up egg yolks is French pastry cream. Yum!
• Add your sugar to the egg whites and use a hand whisk to mix them together.
• Place your bowl on top of the pan of boiling water, making sure the bottom of the bowl doesn’t touch the water. This is called the double-boiler method and is a very gentle way of cooking something or melting something.
• Gently whisk your egg white and sugar mixture for about 3–4 minutes, or until the sugar is completely dissolved and you reach 72°C /160°F. The best way to check that it’s dissolved is by running it through two fingers. If you can’t feel the sugar granules, then it’s time to take it off the heat. If you can feel the granules, continue whisking for another 2–3 minutes and keep testing until you can no longer any granules.
• Transfer the mixture to the bowl of a stand mixer fitted with the whisk attachment and whisk on high speed for about 4–5 minutes. The mixture will become thick and glossy and will begin to cool.
• Gradually add the softened butter, 1 tablespoon at a time, while the mixer is on high speed. At first, your egg whites will deflate and look like the butter is causing them to split, but don’t panic! It will come back together. It takes a couple of minutes for the butter and meringue to become best friends.
• Once you have added all the butter, add the vanilla extract and mix first on low speed to combine, then on high speed for 5 minutes. You’ll know it’s done when the frosting has come together, has turned pale in colour (if you’re making vanilla) and is nice and fluffy.
• If you find your frosting is too aerated, then mix at the lowest speed for about 10 minutes and it will become perfectly smooth again. Alternatively, you can microwave it for 5-10 seconds and use a spatula to gently mix together.