Ingredients:

3 Flour
1/3 Baking Soda
3 Salt
1/2 Mayonnaise
1 1/2 Sugar
1 1/2 Water
1 1/2 Vanilla Extract
1 1/2 Brown Sugar
1 Chocolate Chips
1/3 Half-And-Half
3 Vanilla Extract
1/2 Butter
3 Regular Margarine

Directions:

Preheat oven to 350 degrees F.
In a bowl, sift together the flour, cocoa, baking soda, and salt; set aside.
In the bowl of an electric mixer, combine the mayonnaise and sugar and beat at medium until blended.
With mixer running, gradually add the cold water and vanilla.
Add dry ingredients to mayonnaise mixture, beating until well blended, about 2 minutes.
Pour batter into buttered 13x9x2-inch baking pan.
Bake in 350 degree F oven 40 minutes or until cake tests done.
Cool in cake in pan on rack.,
Meanwhile, begin your Fluffy Chocolate Frosting: In a saucepan over medium heat, combine the brown sugar, half and half or light cream, and butter.
Cook over medium heat, stirring constantly, until mixture comes to a boil; let boil 1 minute, then remove from heat.
Stir in the chocolate chips and vanilla.
Beat with an electric mixer at high speed until the consistency is fluffy and is spreadable.
When cake has cooled, frost it with the Fluffy Chocolate Frosting.
Cut in squares and enjoy! :