1 3/4 c. cake flour
1 c. sugar
1 tsp. salt
2 1/2 tsp. baking powder
1/3 c. butter
2/3 c. milk
1 egg
1 tsp. vanilla

Filling:

5 tbsp. flour
1 egg
1 tsp. vanilla
1 1/2 c. milk

Icing:

1 (1 oz.) sq. unsweetened baking chocolate
1 tbsp. butter
3 1/2 tbsp. boiling water
1 c. confectioners sugar

Preheat oven to 350°F. Grease sides and bottom of 2 (8-inch) spring-form or cake pans.

Sift together flour, sugar, salt and powder; add butter, milk, egg and vanilla and beat for 2 minutes. Pour 1/2 of the batter into each pan.

Bake 25 to 35 minutes.

While cake is cooling, prepare filling. In top of double boiler, set over simmering water, combine sugar and flour. Beat egg with milk and slowly stir into sugar mixture. Cook, stirring frequently until thickened, approximately 20 minutes. Remove from heat. Stir in vanilla and cool to room temperature.

Remove cakes from pans and put on serving plate. Spread custard over 1 of the cakes, then place remaining cake on top.

To prepare the icing, melt chocolate and butter together over very low heat. Remove pan from heat. Stir in boiling water and sugar; beat until smooth. Ice top of cake. Let set. Serve in wedged shaped "pie" slices.