CAN I USE BUTTERMILK INSTEAD?

Since there is no fat in black cocoa powder, I prefer to use whole milk + vinegar in this recipe. If you prefer to use buttermilk, omit the distilled vinegar and use 1 cup of room temperature buttermilk. It is ideal if you can find a higher fat buttermilk.

WHY DOES THIS CAKE RECIPE USE WHIPPED EGG WHITES?

While the instructions are written for the oven, you can easily make this in the toaster oven (toast for 5 minutes) or air fryer (350ºF [177ºC] for 6-8 minutes).

WHAT HAPPENS IF I OVER-WHIP MY EGG WHITES?

Anything more than soft peaks will create too much lift and your cake will rise too much and wrinkle on top after baking. See photos in the post above for visual reference.