This is a really nice sponge cake with a little bit of tang. It manages to have a richness while still being relatively light, with a tight crumb—great for layer cakes or mousse cakes! I use this recipe to make my chocolate mousse cake (recipe under my profile!), so I bake it in 6-inch cake pans. It makes two pretty huge 6-inch cakes, so baking time takes awhile. If you want, you can also bake it in two 8-inch cake pans; the layers will be shorter but will also make a great cake! —Erin McDowell
Preheat the oven to 350° Fahrenheit. Grease and flour two 6-inch cake pans (or two 8-inch cake pans—see note at beginning of recipe).
In the bowl of an electric mixer, whisk the eggs and sugar to combine. Place the mixing bowl over a medium pot of barely simmering water, and whisk until the sugar is dissolved and the mixture is pale and thick, 4 to 5 minutes.
Return the bowl to the mixer, fitted with the whip attachment. Whip on high speed until the mixture is very pale and thick; it should double in volume. Add the vanilla and mix to combine.
In a medium bowl, whisk the flour, baking powder, baking soda, and salt to combine.
Add the sour cream to the mixer and whisk until fully incorporated. Add the flour gradually, mixing just until combined and fully incorporated.
Divide the batter between the prepared pans and bake until a toothpick inserted into the center comes out clean, 50 to 55 minutes (for 6-inch pans).
I always carry three kinds of hot sauce in my purse. I have a soft spot for making people their favorite dessert, especially if it's pie. My first cookbook, The Fearless Baker, is out on October 24, 2017.