Put flour, soda, salt, and cocoa in large mixing bowl. Set aside.
Beat mayo, sugar, water and vanilla until creamy. Add dry ingredients slowly and beat well.
Preheat oven to 350 degrees F. Prepare either 2 - 10" round pans, or put into oblong pan. Cook 30 to 40 minutes or until toothpick comes out clean.
Mix butter, cocoa, powdered sugar, vanilla, and salt together with some milk. Stir to get all lumps out. Add more milk if too thick.
Calories From Fat
% Daily Value*
Total Fat 0g
Saturated Fat 0g
Trans Fat 0g
Dietary Fibers 0g
* Percent Daily Values are based on a 2,000 calorie diet.
* Nutrition information is estimated based on the ingredients and cooking instructions as described in each recipe and is intended to be used for informational purposes only. Please note that nutrition details may vary based on methods of preparation, origin and freshness of ingredients used.