Unsalted butter, softened for pans
cup unsweetened Dutch cocoa powder, plus more for pans
cup all-purpose flour
tsp. baking soda
cup warm water
tbsp. safflower oil
tsp. vanilla extract
1. Preheat oven to 350F. Butter 2 8-inch round bake pans (2"deep); dust with cocoa. Sift cocoa, flour, sugar, baking soda, baking powder and salt into the bowl of a mixer. 2. Beat on low speed until just combined. Raise speed to medium, and add eggs, buttermilk, water, oil and vanilla. Beat until smooth (3min) 3. Divide batter between pans. Bake until set and a toothpick inserted into the center comes out clean, about 35 minutes. Let cool for 15 minutes. Turn out from pans. Transfer, faceup, to wire racks. Let cool completely. 4. Spread 2 cups chocolate frosting onto top of 1 cooled layer. Top with remaining layer, frost top and sides.