4 squares (4 oz.) unsweetened chocolate
1 3/4 c. sugar
2 c. all-purpose flour
1 tbsp. baking powder
1/2 c. cooking oil
7 egg yolks
1 tsp. vanilla
7 egg whites
1/2 tsp. cream of tartar
Custard Filling
Chocolate Icing
Vanilla Icing

Melt chocolate; stir in 1/4 cup of the sugar and 1/2 cup boiling water; cool. Combine flour, remaining sugar, baking powder, and 1 teaspoon salt. Add oil, egg yolks, vanilla, and 3/4 cup cold water all at once; beat until smooth. Stir in chocolate mixture.

Combine egg whites and cream of tartar; beat until stiff peaks form. Pour chocolate mixture in a thin stream over entire surface of egg whites; fold in gently. Turn into a 10-inch tube pan; bake in a 325 degrees oven for 65 minutes. Invert pan to cool; remove from pan.

Make Custard Filling. Split cake into 3 layers. Fill with filling. Prepare icings. Frost top with Chocolate Icing. Pipe 4 concentric circles of Vanilla Icing on top; draw spatula through icing for web. Chill. Makes 12 to 16 servings.

CUSTARD FILLING:

Combine 1/4 cup cornstarch and 1/4 cup sugar. Stir in 3 cups milk; cook and stir until bubbly. Reduce heat; cook and stir for 2 minutes more. Add 1 cup of the hot mixture to 2 beaten eggs; return all to pan. Cook and stir until slightly thickened; reduce heat. Cook and stir for 1 to 2 minutes more but DO NOT BOIL. Stir in 2 teaspoons vanilla. Cover surface with waxed paper; cool

CHOCOLATE ICING:

In a saucepan, melt 1 (4 oz.) package German sweet cooking chocolate and 3 tablespoons butter over low heat, stirring often. Remove from heat; stir in 1 1/2 cups sifted powdered sugar and enough hot water (3 to 4 tablespoons) to make of drizzling consistency.

VANILLA ICING:

Stir together 2 cups sifted powdered sugar, 1 teaspoon vanilla, and a dash of salt. Stir in enough milk (2 to 3 tablespoons) to make of piping consistency.