No Egg Chocolate Cake {Hundred Dollar Cake}

I love this recipe for those days when there isn't an egg to be found in the house.

A very moist chocolate cake due to the mayonnaise base, with a very rich frosting. The name of the cake comes from the story that somebody (I think around the turn of the last century) supposedly paid $100 to a restaurant in Chicago for the recipe--equivalent to paying several thousand dollars today. 

2 c. flour
1 c. sugar

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

Sift together dry ingredients and add water, mayonnaise and vanilla. Bake in greased pans 30 to 35 minutes at 350 degrees.