Boston Cream Sponge Cake

Directions

• In a large bowl, beat eggs until lemon-colored. Gradually add sugar and salt, beating until thick and lemon-colored. Beat in vanilla. Fold in flour, 2 tablespoons at a time. Pour into two greased and floured 9-in. round baking pans.
• Bake at 350° for 17-20 minutes or until cake springs back when lightly touched. Cool for 10 minutes before removing from pans to wire racks to cool completely.
• For custard, combine sugar and cornstarch in a saucepan. Gradually stir in milk until smooth. Bring to a boil; cook and stir for 2 minutes. Remove from the heat. Stir a small amount of hot mixture into egg yolks; return all to the pan. Bring to a gentle boil, stirring constantly. Remove from the heat; stir in vanilla. Cool completely.
• In a large bowl, cream butter until light and fluffy. Gradually beat in custard.
• Cut each cake horizontally into two layers. Place bottom layer on a serving plate; top with a third of the filling. Repeat layers twice. Top with remaining cake layer.
• In a small bowl, combine frosting ingredients. Spread over top of cake. Refrigerate.