Vanilla Frosting

I N G R E D I E N T S
350g reduced aquafaba or 700g unreduced aquafaba
675g granulated sugar
1/2 tsp cream of tartar
1/4 tsp xanthan gum
800g stick butter
1 tbsp vanilla bean paste

I N S T R U C T I O N S

1. If necessary, reduce 700g aquafaba to 350g.
2. Combine aquafaba and sugar in a metal bowl or double boiler. Place over boiling water and whisk until sugar is dissolved. You can check by touching some of the mixture on the whisk and feeling if it's grainy. Once it's smooth, you're done.
3. Transfer to stand mixer with whisk attachment. Add the cream of tartar and xanthan gum. Whisk on high for about 10 minutes, or until the meringue reaches stiff peaks. (If it stays runny, it's honestly... fine. Just keep going. It'll fluff up with the butter.)
4. Turn the stand mixer to low and add the butter, a small amount at a time (cut it into cubes or something). Also add the vanilla.
5. Turn the stand mixer to high and whisk for about 10 minutes. If it looks split, don't worry, just keep whisking.

NOTE: This makes a lot of frosting. It’ll be enough to frost two 8”, three layer cakes somewhat generously (a good amount of frosting on the outside, between layers, and some decoration). If you want to add a lot of buttercream decorations, you should make 125% of this for two 8” three layer cakes.