Easiest Swiss buttercream
Ingredients
3 Sticks unsalted butter
4 Egg whites
1 Cup sugar (caster sugar everywhere else, regular sugar in the US)
1/4 Cup lemon juice
1 Teaspoon vanilla essence
Place the egg whites and sugar in your mixer bowl (make sure it is squeaky clean after making your cake, and dry it out otherwise it won’t whip up!) and put that on a double boiler.
Use a clean hand whisk and start whisking. The goal here is to get the sugar melted so you don’t have any graininess left. Whisk away for about 2-3 mins. The eggs will start to get thick and marshmallow-ey but it doesn’t matter if they don’t- they just mustn’t cook, you just want to melt the sugar.
Take the bowl off the heat and put on your mixer and attach the whisk. Start whisking it on up on high until the bowl is completely cool. This takes 7-10 mins.
Swap to the paddle attachment and start adding the butter, 1 tablespoon at a time. The butter must be room temperature or the buttercream will curdle.
Slowly trickle in the lemon juice and vanilla essence. It may curdle now but should come back together. Dip your finger in - did you ever taste a buttercream so light and lemony and delicious??
