Chocolate Mayonnaise Cake with German Chocolate Frosting

Chocolate cake with chocolate buttercream and German Chocolate frosting

Dense, chocolaty, made-from-scratch mayonnaise cake with chocolate buttercream and German chocolate frosting.  An indulgent celebration cake for sure!

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mayonnaise cake with chocolate buttercream and German Chocolate frosting

For as long as I can remember, I’ve baked birthday cakes for my family. Of course, back in the day it was a plain 9×13 inch cake from a box with a can of frosting slathered on top. (My sister and I may or may not have used the minimum amount of frosting on the cake in order to be able to eat the rest of the can…). I think taking the time to bake up something sweet for your loved ones on their birthday really shows them how much you love them. I know it makes my heart swell every year when my mom brings me her homemade angel food cake.

Mayonnaise cake is one of the few cakes that I make from scratch and pretty much the only chocolate cake my family will eat (unless you’re my nephew who will eat any and every chocolate cake available). It’s what I would call and “old fashioned” cake-dense and fudgy, so be sure you have a tall glass of milk to go alongside it.

Random side note-it feels like we all decorate our “German chocolate cake ” kind of the same-if you do a Pinterest search, everyone is a big fan of the chocolate buttercream with the coconut pecan frosting on the top and some good ole 1M swirls. I guess if it works, it works!

This cake is a one bowl, mix with a spoon in about 15 minutes kind of cake, but don’t think she’s not fussy in her own way. The recipe does not double or triple. I made that mistake once and it basically exploded when I went to turn it out of the pan. There was much swearing. It’s meant to be a small cake.

Chocolate cake with chocolate buttercream and German Chocolate frosting

Mayonnaise Cake

Prep Time 15 minutes
Cook Time 35 minutes
Total Time 50 minutes
Servings 8 people


  • 2 cups all-purpose flour sifted
  • 1 cup sugar
  • 4 tablespoons cocoa powder
  • 2 teaspoons baking soda
  • 1 teaspoon vanilla extract
  • 1/2 teaspoon salt
  • 1 cup mayonnaise
  • 1 cup hot water


  • Heat your water.  I usually put my tea kettle on while I’m getting the other ingredients ready in the bowl and it’s nice and hot by the time I need it.
  • In a large bowl, sift flour, sugar, and cocoa powder adding them one on top of the other.  
  • Add in baking soda, salt, vanilla extract, and mayonnaise.
  • Pour hot water over ingredients.
  • Stir until all the batter is mixed together and you don’t have any flour streaks.  Flour may get a little bit lumpy, don’t worry about it.
  • Pour batter into greased 9×9 pan.  Or you can use a 9 inch round or a 8 inch round as long as they are at least 2 inches tall.  
  • Bake at 350 degrees for 35 minutes or until you insert a toothpick and it comes out with just crumbs.  Chocolate cakes are tricky to try and tell when they are done because you can’t see how brown they are getting so it’s easy to over bake them.  I usually start checking mine at 30 minutes.
  • Cool on a cooling rack for 15 minutes and then turn out of the pan.  Allow to cool for at least 1-2 hours before frosting.  I like to refrigerate my cakes overnight before frosting because I think frosting a cold cake makes life a whole lot easier.


Do not use Miracle Whip instead of mayonnaise!  It will not work!  Miracle Whip has less oil than real mayonnaise and we are using it for the oil and egg content.
Makes only one “layer” of cake.  If you want a two layer cake, you need to mix the batter twice.  For some reason, this recipe does not lend itself well to doubling.  
This is a heavier cake since it uses all-purpose flour, so it also does not do well in a large pan.  It will collapse on itself when you turn it out of the pan.  Ask me how I know.

Chocolate Buttercream

Easy to make, soft, American style chocolate buttercream perfect for any cake or cupcakes.
Course Dessert
Keyword buttercream


  • 1 sticks salted butter softened (1 pound)
  • 8 cups powdered sugar (2 pound bag)
  • 1 1/2 cups cocoa powder
  • 1/2 cup heavy cream
  • 1/4 cup water as needed


  • Beat butter on high speed until smooth.
  • Slowly beat in powdered sugar and cocoa powder.  As mixture becomes thick, add in heavy cream.
  • If buttercream is still thicker than desired, add water while mixing, 1 tablespoon at a time until desired consistency is reached.  


  • Don’t add the whole amount of water at once.  Just add it one tablespoon at a time.  You think you are going to save time, you are not.  You are going to have soupy buttercream on your hands.
  • For chocolate buttercream with a little bit something extra, substitute strong brewed coffee for the water portion.  
  • For a peanut butter chocolate buttercream, use 1 cup of peanut butter in exchange for 1 cup of butter (2 sticks).

German Chocolate Frosting

Slightly adapted from Yammie’s Noshery
Sweet coconut pecan frosting that cooks up quickly and easily on the stove.
Course Dessert
Keyword frosting
Prep Time 5 minutes
Cook Time 10 minutes
Total Time 15 minutes
Servings 1 cake


  • 1 cup brown sugar
  • 1 cup evaporated milk
  • 3 large egg yolks lightly beaten
  • 1/2 cup butter
  • 1 teaspoon pure vanilla extract
  • 1 package sweetened flaked coconut (7 ounces)
  • 2 cups pecans roughly chopped


  • In a medium saucepan over medium heat (so much medium!) stir together milk, butter, brown sugar, and egg yolks.  
  • Stir constantly until mixture is thickened.  If you don’t stir the mixture, the eggs will have a tendency to clump up, like scrambled eggs.  You want to dilute the egg mixture so the proteins can’t bind together.
  • Once mixture has thickened, remove from heat.
  • Stir in vanilla, coconut, and pecans.  Allow to cool before frosting cake.


Yammie’s Noshery

Cooks IllustratedCooks Illustrated

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