3 eggs
1 egg white (save yolk for filling)
2 tbsp. cocoa
3/4 c. sugar
1/3 c. flour
2 tsp. baking powder

Beat eggs, egg whites and sugar until light and fluffy. Sift flour, cocoa, baking powder together. Stir well. Grease pan, 10 x 15 inch, line with wax paper and grease wax paper. Pour batter. Bake 10 minutes in 400 degree oven. Turn out cake on powdered sugared wax paper. Let cool.

Filling: 6 tablespoons soft butter and 1 cup powdered sugar. Cream until light and fluffy. Stir in 1 egg yolk and 1 teaspoon vanilla. Spread on cake. Roll up. Store in refrigerator.