2 sticks butter
1 cup + 3 tbsp sugar
1 1/2 cups all-purpose flour
1/2 cup + 3 tbsp unsweetened cocoa
1 tbsp baking powder
1/2 tsp baking soda
1 tsp salt
4 large eggs
3/4 cup very hot water
1 cup heavy cream
10 1/2-oz semisweet chocolate
6 oz white chocolate for garnish, optional
If using white chocolate for garnish, finely grate onto a plate using a vegetable peeler. Chill until needed.
Preheat oven to 350 degrees.
Grease bottoms of two 8-inch round cake pans and line with parchment paper; set aside.
In a large mixer bowl, combine the butter, sugar, flour, cocoa, baking powder, baking soda, salt and eggs. Beat until smooth with mixer at medium speed; then beat another 2 minutes. Add the hot water and beat to blend well, about 1 minute. Divide the batter evenly between the two prepared pans.
Bake at 350 degrees for 20 to 25 minutes until a wooden toothpick inserted in the center comes out clean. Cool in the pans for 10 minutes. Turn cakes out onto wire racks and remove the parchment paper; cool comletely.
While cakes cool, heat the heavy cream just to boiling. Break the chocolate into pieces and add to the cream; stir until chocolate is melted. Let cool and then refrigerate for 30 minutes. Remove from refrigerator and whisk with a wire whisk until of spreading consistency.
Use about a third of the frosting as a filling between the two layers. Use remaining frosting to cover sides and top of cake. Sprinkle the grated, chilled white chocolate over the top, if desired.