Double Chocolate Cake

Cake Ingredients:

Butter, for greasing the pans

1 3/4 cups all-purpose flour, plus more for pans

2 cups sugar

3/4 cups good cocoa powder

2 teaspoons baking soda

1 teaspoon baking powder

1 teaspoon kosher salt

1 cup buttermilk, shaken

1/2 cup vegetable oil

2 extra-large eggs, at room temperature

1 teaspoon pure vanilla extract

1 cup freshly brewed hot coffee

Preheat the oven to 350 degrees F. Butter 3 (8-inch) round cake pans. Line with parchment paper, then butter and flour the pans.

Sift the flour, sugar, cocoa, baking soda, baking powder, and salt into the bowl of an electric mixer fitted with a paddle attachment and mix on low speed until combined. In another bowl, combine the buttermilk, oil, eggs, and vanilla. With the mixer on low speed, slowly add the wet ingredients to the dry. With mixer still on low, add the coffee and stir just to combine, scraping the bottom of the bowl with a rubber spatula. Pour the batter into the prepared pans and bake for 35 to 40 minutes, until a cake tester comes out clean. Cool in the pans for 30 minutes, then turn them out onto a cooling rack and cool completely.

Place 1 layer, flat side up, on a flat plate or cake pedestal. With a knife or offset spatula, spread the top with frosting. Place the second layer on top, rounded side up, and spread the frosting evenly on the top and sides of the cake.

Icing:

3 1/2 ounces milk chocolate

3 ounces semisweet chocolate

2 cups confectioners' sugar, sifted

1/4 cup milk

1/4 cup (1/2 stick) unsalted butter, softened

2 teaspoons pure vanilla extract

1/4 teaspoon salt

Directions:

Put the chocolates in a medium heatproof bowl. Bring a saucepan filled with 1 inch or so of water to a very slow simmer; set the bowl over, but not touching, the water. Stir the chocolate occasionally until melted and smooth. (Alternatively, put the chocolate in a medium microwave-safe bowl. Melt at 50 percent power in the microwave until soft, about 1 minute. Stir, and continue heat until completely melted, about 1 to 2 minutes more.)

Add the confectioners' sugar, milk, butter, vanilla extract, and salt and beat with an electric mixer until smooth and creamy.