2 c. flour
1 c. sugar
2 tsp. baking soda
1/2 c. cocoa
1/4 tsp. salt
1 c. mayonnaise
1 c. cold water
1 tsp. vanilla

Mix dry ingredients together then add the rest. Blend well. Pour batter into greased 9 x 13 pan.

Bake at 350°F for 30 minutes or until toothpicks comes out clean.