Boston Cream Sponge Cakes

Directions

1. In a small bowl, beat eggs until light and fluffy. Gradually add sugar and salt, beating until thick and lemon-colored, about 5 minutes. Stir in vanilla. Fold in flour, 2 tablespoons at a time.
2. Gently spoon into two 4-in. springform pans coated with cooking spray (pans will be full). Bake at 350° for 15-20 minutes or until cake springs back when lightly touched. Cool for 10 minutes before removing from pans to a wire rack to cool completely.
3. For custard, in a small saucepan, combine sugar and cornstarch. Stir in milk until smooth. Cook and stir over medium heat until thickened and bubbly. Reduce heat; cook and stir 2 minutes longer. Remove from the heat. Stir a small amount of hot filling into egg yolks; return all to the pan, stirring constantly. Bring to a gentle boil; cook and stir 2 minutes longer.
4. Remove from the heat. Gently stir in vanilla. Cool to room temperature without stirring. In a small bowl, cream butter. Gradually beat in custard.
5. To assemble, cut each cake horizontally in half. Place bottom layers on two serving plates; spread with filling. Replace cake tops. In a small bowl, beat the frosting ingredients. Spread over top of cakes. Refrigerate until serving.