227g (1 cup) unsalted butter, softened at room temperature
232g (~1 cup, tightly packed) light brown sugar
210g (~1 cup) granulated sugar
150g (~3 large) eggs, at room temperature
246g (~2¼ cups) cake flour
5g (1 teaspoon) baking soda
4g (1/2 teaspoon) salt
240 milliliters (1 cup) buttermilk
Vanilla Buttercream (see below)
Whipped Chocolate Buttercream (see below)
Instructions
Pre-heat oven to 350 degrees
Grease and flour two 9-inch round pans and line bottoms with parchment paper
In a medium heat-proof bowl, combine the cocoa powder, espresso powder and chocolate; pour boiling water over mixture and whisk together until melted and smooth; stir in vanilla; set aside to cool
In the large bowl of an electric mixer with paddle attachment, beat butter until light and creamy; add sugars and beat on medium speed until light and fluffy; add eggs, one at a time, mixing at medium speed between each
Sift cake flour, baking soda and salt into a medium bowl and set aside
Whisk buttermilk into cooled chocolate mixture
Add about ⅓ of the flour mixture to mixing bowl and mix on low speed just until combined; add half of chocolate mixture and mix on low again, just until combined; scrape the sides of the mixing bowl and repeat with ⅓ of flour mixture remaining chocolate mixture; remove bowl from mixer and fold in remaining dry ingredients; be careful not to overmix the batter
Pour batter into prepared pans and bake for 30-35 minutes or until a toothpick comes out clean from center of cakes
Set cake layers aside to cool for 10 minutes then carefully remove each layer from pans; run a knife around the edge of each layer for easier removal
Once cake layers are completely cooled, use a serrated knife to carefully cut each layer in half horizontally, creating 4 cake layers; set aside and make buttercreams
Notes
Cake barely adapted from Sticky, Chewy, Messy, Gooey Store cake in refrigerator and serve at room temperature; best eaten within three days
Recipe by Keep It Sweet Desserts at http://www.keepitsweetdesserts.com/fudgy-black-and-white-devils-food-cake/