1 c. butter
1/2 c. shortening
3 c. sugar
5 eggs
1 c. sour milk with 1/2 tsp. baking soda
1 tsp. vanilla
3 c. flour
5 tbsp. cocoa
1/2 tsp. salt
1/2 tsp. baking powder

Cream shortening, butter and sugar. Add eggs and beat. Sift dry ingredients. Add alternately with milk and vanilla.

Bake in angel food cake pan at 325°F for 80 minutes.