Chocolate Mayonnaise Snacking Cake

A slice of chocolate mayonnaise cake on a plate, with the remaining cake in a pan next to it.

Chocolate Mayonnaise Snacking Cake

This chocolate mayonnaise cake is a simple and easy recipe based on a vintage recipe using mayonnaise in place of eggs and butter/oil. The result is a moist and plush cake that comes together quickly in one bowl. I paired it with an easy-to-make chocolate sour cream frosting but you can just dust it with powdered sugar if you want something simpler.

Course coffee time, Dessert, Snack

Cuisine American

Keyword cake, chocolate, easy

Prep Time 25

Cook Time 25

Servings

Calories 899kcal

Author Irvin

Ingredients

Cake Batter

1 1/4 cup hot water 300 ml or 300 g (or fresh brewed coffee)
1 teaspoon instant coffee or espresso powder (optional but recommended, skip if using coffee instead of water)
3/4 cup natural cocoa powder 65 g (see section above for about cocoa powder and substituting Dutch-processed cocoa)
2 1/4 cups all-purpose flour 315 g
1 cup white granulated sugar 200 g
1/4 cup packed dark brown sugar 55 g
2 teaspoon baking powder
1/2 teaspoon baking soda
1/2 teaspoon kosher salt
1 1/4 cups mayonnaise 300 g
2 teaspoons vanilla extract

For Pan

1 tablespoon butter melted

Frosting

6 1/4 ounces dark chocolate chopped (175 g)
6 tablespoons unsalted butter 85 g
2 1/2 cups confectioner’s sugar sifted, 290 g
1/2 cup sour cream 125 ml or 125g
1 tablespoon corn syrup optional, see note below
2 teaspoons vanilla extract

Instructions

Preheat the oven to 350°F.
Make the cake by measuring out the hot water (or fresh brewed coffee) into a 2-cup glass measuring cup or small bowl. Add the instant coffee or espresso powder and the cocoa powder to the liquid and stir to dissolve the cocoa powder.
Place the flour, white sugar, brown sugar, baking powder, baking soda, and salt into a large bowl. Whisk all the dry ingredients together.
Add the chocolate coffee liquid, mayonnaise, and vanilla to the bowl. Stir with a whisk breaking up any big clumps, until a smooth batter forms.
Brush the bottom and sides of a 9 x 13 x 2-inch pan with the melted butter.
Pour the batter into the pan, smoothing it out so you have an even layer.
Bake in the oven for 25 to 30 minutes, or the sides of the cake pull away from the pan a little bit, the top of the cake starts to crack slightly, and a toothpick inserted in the center of the cake comes out clean.
Let cool in the pan for two hours, or until it gets to room temperature before frosting.
Make the frosting by placing the dark chocolate and butter in a microwave-safe bowl. Melt the two together, cooking in 30 second intervals, stirring between each cooking cycle, until both chocolate and butter are melted and smooth.
Sift in the confectioner’s sugar (do not skip this test, as lump confectioner’s sugar does not dissolve, and you’ll end up with lumpy frosting). Add the sour cream, corn syrup (if using) and vanilla. Stir it all together with a balloon whisk until smooth.
Once the cake is cooled to room temperature, ice the top of the cake with the frosting.

Notes

The corn syrup in the frosting adds a sheen and gloss. You can substitute honey (though this will add a slight honey flavor to the frosting) or you can skip it all together, though the frosting will look less shiny.

Nutrition