Devil's Food Cake

a simple, velvety chocolate cake... the perfect dessert (pictured here with peppermint frosting).

4 oz unsweetened baker's chocolate, chopped
1/4 cup baker's cocoa (Dutch-processed if possible)
1 1/4 cup boiling water
3/4 cup all-purpose flour
3/4 cup plain cake flour
1 tsp baking soda
1/4 tsp salt
2 sticks (1 cup) butter, softened but still cool
1 1/2 cups packed brown sugar
3 large eggs, room temp
1/2 cup sour cream or plain yogurt
1 tsp vanilla

1. preheat oven to 350° with rack in the middle position. meanwhile, grease two 9-inch round cake cans and line the bottom of each pan with waxed or parchment paper.
2. whisk flour, baking soda, and salt in a medium bowl, set aside. combine the chocolate and cocoa in a medium-small bowl; pour boiling water over and whisk until smooth, 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 one at a time, beating until combined after each one. add sour cream (or yogurt) and vanilla and beat until combined.
4. on low speed, add a third of the flour mixture, then half of the chocolate mixture. then another third of the flour, the other half of the chocolate a finally the last third of the flour just until combined each time. do not over beat. scrape sides and bottom of bowl again and stir gently to thoroughly combine.
5. divide batter evenly into pans and bake for 20-23 minutes until inserted toothpick comes out clean. cool cakes in pans for 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. frost with chocolate, vanilla, peppermint, or Nutella* frosting.

frosting
1/4 cup butter, softened
2 cups powdered sugar
pinch salt
2 Tbsp milk
2 tsp vanilla or 1/2 tsp peppermint extract

beat butter in a small bowl until light a fluffy. add 1 cup powdered sugar, salt, vanilla and 1 Tbsp milk. mix slowly as the sugar incorporates then faster as is becomes smooth. add remaining sugar and milk and repeat mixing. beat until smooth and creamy. add more sugar or more milk to achieve desired consistency (but no more than 1/4 sugar or 1 tsp milk).

* to make Nutella frosting, follow standard frosting recipe adding 1/4 cup Nutella after first addition, and mixing of sugar and milk. continue with the rest of the sugar and milk.