Swiss Meringue Buttercream is smooth, silky, and not tooth-achingly sweet. It can be used on a variety of cakes and cupcakes as it can easily be flavored. For this recipe, I am using vanilla, but chocolate, espresso powder, fruit purees, caramel, and lemon zest are excellent alternatives too!
- 150 milliliters egg whites ((approximately from 5 large eggs))
- 250 grams granulated white sugar
- 450 grams unsalted butter, at room temperature ((cut into small cubes))
- 2 1/2 teaspoons pure vanilla extract
- In a metal bowl, put the egg whites and sugar. Whisk by hand. Put the bowl over a saucepan (to create a double boiler) with simmering water. Whisk until it registers 160 F or 70 C on a candy thermometer.
- Transfer the mixture in a stand mixer bowl and beat with whisk attachment on high speed for about 8-10 minutes or until medium-stiff peaks.
- Switch to paddle attachment and on low speed, add the vanilla extract then the cubes of butter a few at a time. Once incorporated, turn up the speed to medium-high until smooth and silky, about 3-5 minutes. Please see recipe notes about curdling.
This recipe is enough to fill and frost a three-layered 8-inch cake.
After adding all the butter the frosting might look curdled. This is okay! Just continue mixing for another 5 mins at medium-low speed (I used speed 4 for my Kitchen Aid mixer) and watch it turn from curdled to silky smooth.