The Brilliant Secret to the Most Tender Cake Is Already in Your Fridge

I was in fourth grade, and our formidably grumpy teacher Miss Hale uncharacteristically brought in a chocolate cake for the class. After we devoured our small squares of cake from tiny paper napkins, Miss Hale announced the cake had a secret ingredient: mayonnaise. It blew our young minds. Some kids performatively made yuck sounds, but most of us simply yearned for more cake.

Now that I’m an adult, I can surmise Miss Hale’s ruse. America probably has more chocolate cake lovers than mayonnaise lovers. And mayonnaise haters? We have millions. But even the most vocal of the anti-mayo camp would be hard pressed to find a chocolate mayonnaise cake anything but irresistible. I dare you to bake our chocolate mayonnaise sheet cake and not fall to its rich, chocolatey allure. It’s a dead easy recipe with a silky frosting that’s downright sexy.

Mayonnaise in Cake Is a Thing

Food manufacturers in recent years have found that touting outrageous uses for their products scores plenty of cheap publicity. Behold: Hellmann’s frozen mayo-nog cocktail. I suggest a far superior use for your mayonnaise. Cake. I’ll take a mayonnaise cake over frozen mayo-nog any day.

The first known written recipe for mayonnaise cake dates back to 1927; it’s a lightly spiced date-nut cake with a touch of chocolate. Thrifty cooks have always looked upon inspired ingredients when certain items were scarce–outside of mayonnaise cakes, there are cake sub-genres starring tomato soup, ground salt pork, sauerkraut, and various types of soda, such as 7-Up and Dr. Pepper. The mayonnaise cake rose to prominence in the late 1930s, when companies began sharing mayonnaise recipes in pamphlets and touting that it could conveniently stand in for butter and milk or other dairy. These were in short order during World War II, but there’s also the novelty appeal of using a savory condiment in a decidedly sweet cake.

What Does Mayonnaise Add to a Cake?

From a baking science standpoint, adding mayonnaise to a cake totally makes sense, very much the way adding butter, sour cream, milk, or buttermilk makes sense. It’s simply in an unexpected delivery system.

Let’s break mayonnaise down to its essentials. Mayo = oil, acid, and eggs. Oil is by far the prominent ingredient, so when you add mayonnaise to a cake, you’re mostly adding fat. The egg component in mayo is small enough that adding fresh eggs to the batter is still necessary. As for acid (present in mayonnaise via vinegar or lemon juice), it contributes a pleasant tang and tenderizing effect, much as buttermilk or sour cream would—two dairy ingredients commonly found in recipes for moist cake recipes.

Can You Use Mayonnaise in Boxed Cake Mix?

Heck yes! The ingredients you add to cake mix are often oil, eggs, and water. The go-to Best Foods recipe (a.k.a. Hellmann’s, depending on where you live) calls for one box of yellow cake mix, 1 cup of mayonnaise, 1 cup of water, and 3 eggs—mayonnaise does not have a ton of liquid, so more liquid is added to the cake mix. Though the recipe calls for yellow cake mix, get creative and try other flavors, too.