This is a combination of Hershey's "Perfectly Chocolate Cake" and the Devil's Food Cake from America's Test Kitchen—the best of both worlds.
1 cup all-purpose flour
3/4 cup plain cake flour
1 1/2 tsp baking powder
1 1/2 tsp baking soda
1/2 tsp salt
1 1/2 sticks (12 Tbsp) butter, softened
1 3/4 cups packed brown sugar
3 large eggs, room temp
2 tsp vanilla
1/2 cup sour cream or plain whole milk yogurt
1/2 milk
1 cup cocoa powder
1 1/4 cup boiling water
1. Preheat oven to 350° with rack in the middle position. Grease (and flour) two 9-inch round cake cans and line the bottom of each pan with waxed or parchment paper.
2. Whisk flour, baking powder, baking soda, and salt in a medium bowl, set aside.
3. Beat butter in a medium bowl at medium-high speed until creamy, about 1 minute. Add the brown sugar and beat at hight speed until light and fluffy, about 3 minutes. Scrape down the bowl with a rubber spatula. add eggs, beat until combined. Add sour cream (or yogurt), milk and vanilla and beat until combined.
4. On low speed, add cocoa powder until combined. Add the flour mixture just until combined (do not over beat). Scrape sides and bottom of bowl again, and stir boiling water in to thoroughly combine.
5. Divide batter evenly into pans and bake for 26-30 minutes until inserted toothpick comes out clean. Cool cakes in pans for 10-15 minutes. Run a knife around the edge of each pan and invert cake onto a plate. Peel off the paper and re-invert onto a wire rack. Cool completely and frost.
