As I said there are many recipes for Chocolate Mayonnaise Cake. Here are two Retro recipes for Hellmann's Chocolate Mayo Cake and a newer recipe for a Chocolate Mayonnaise Bundt Cake. I have found several of these ads over the years--some recipes use eggs and some don't. I think the earlier recipes must be from the 30s and early 40s.
Mayonnaise Cakes are really moist, so it's hard to go wrong on any of these recipes.
Want to try a variation of the recipes above? Use Miracle Whip instead of Mayonnaise. Totally different flavor. Most people are particular when it comes to the choice between Mayonnaise and Miracle Whip. I still think it's worth trying Miracle Whip in this chocolate cake recipe... or for that matter, in the bundt cake recipe below. Word to the wise: don't taste the batter before it's baked. It will seem a bit odd, but the final results will be delicious.
And, just for good measure, here's a third recipe for Chocolate Mayonnaise Cake!
Chocolate Mayonnaise Bundt Cake
1 cup sugar
2 cups flour
6 Tbsp dark cocoa
2 tsp baking soda
1 tsp vanilla (or whatever you have)
1 cup mayonnaise (or Miracle Whip)
1 egg, whipped
1 cup lukewarm water
1 cup chocolate chips or chopped dark chocolate 70% or higher cacao
Blend dry ingredients.
Mix in vanilla, mayonnaise, egg, and water-- just enough to get all ingredients blended.
Fold in chocolate chips (broken up chocolate)
Pour into greased Bundt pan.
Bake at 375 degrees for about 35 minutes or until toothpick comes out clean.
Dust with powdered sugar.