3 c. unsifted flour
1 1/2 c. sugar
1/3 c. cocoa
2 1/4 tsp. baking powder
1 1/2 tsp. baking soda
1 1/2 c. mayonnaise
1 1/2 c. water
1 1/2 tsp. vanilla

Grease cake pan. Sift together dry ingredients into large bowl. Stir in mayonnaise. Gradually stir in water and vanilla until smooth and blended. Pour into prepared pan. Bake in 350 degree oven about 30 minutes.