3 oz. unsweetened chocolate
1 cup (2 sticks) unsalted butter, at room temperature
2 1/4 cups packed dark brown sugar
3 eggs
2 1/4 cups cake flour
2 tsp. baking soda
1/2 tsp. salt
1/2 cup buttermilk
1 cup boiling water
Chocolate Icing

Preheat oven to 375°F. Grease and flour two 9-inch cake pans.

Place chocolate in small, heavy saucepan and melt over low heat, stirring constantly. Remove the pan from heat and set it aside.

Beat butter and brown sugar together in a bowl with an electric mixer.

With mixer on low speed, add the eggs, one at a time, beating well after each addition. Stir in the melted chocolate.

Combine cake flour, baking soda, and salt. Alternating between the two, add the flour mixture and buttermilk to the chocolate mixture in 3 stages, ending with flour. Then slowly stir in the boiling water and vanilla.

Pour the batter into 2 prepared pans, and bake until toothpick inserted in the center of a layer comes out clean, about 30 minutes.

Remove pans from oven and let layers sit for 5 minutes. Then invert the pans over wire racks, releasing the cake and let cake cool completely.

CHOCOLATE ICING:

1 1/2 cups semi-sweet chocolate morsels
8 tbsp. (1 stick) unsalted butter, at room temperature
2/3 cup milk
1 tsp. vanilla extract
1 cup confectioners' sugar

Combine the chocolate and butter in a small, heavy saucepan and melt over very low heat. Remove the pan from the heat; stir in the milk and vanilla and transfer the mixture to a mixing bowl. Add the sugar gradually, beating with an electric mixer. Continue beating until the mixture is smooth; it will be runny.

Refrigerate the mixture for 1 hour, beating it every 15 minutes. The icing will stiffen.

About 2 1/2 cups.