The Secret to the Moistest Chocolate Cake You'll Ever Bake

Have you ever wondered how bakeries achieve that incredibly moist, rich chocolate cake that stays soft for days? The secret ingredient might surprise you: mayonnaise! This chocolate mayo cake transforms a pantry staple into the most decadent dessert you'll make at home. Making your own chocolate mayonnaise cake is not only cost-effective but also allows you to control ingredients, avoid preservatives, and create a show-stopping dessert that rivals any bakery creation. The mayo replaces eggs and oil, delivering unmatched moisture and a tender crumb that will have everyone asking for your secret.

Ingredients List

    • 2 cups all-purpose flour
    • 1 cup granulated sugar
    • ¾ cup unsweetened cocoa powder
    • 2 teaspoons baking soda
    • 1 teaspoon baking powder
    • ½ teaspoon salt
    • 1 cup full-fat mayonnaise
    • 1 cup warm water
    • 2 teaspoons vanilla extract

For the Chocolate Frosting:

    • ½ cup unsalted butter, softened
    • ⅓ cup unsweetened cocoa powder
    • 3 cups powdered sugar
    • ¼ cup whole milk
    • 1 teaspoon vanilla extract
    • Optional: ¼ teaspoon espresso powder for deeper flavor

Timing / Cooking Schedule

Prep time: 15 minutes

Cooking time: 30 minutes

Total time: 45 minutes

This recipe is faster than most from-scratch cakes because mayonnaise eliminates the need for creaming butter or separating eggs. You can have this cake baked and cooled while preparing frosting—perfect for last-minute celebrations.

Step-by-Step Instructions

Step 1: Preheat and Prepare Preheat your oven to 350°F (175°C). Grease two 9-inch round cake pans and line the bottoms with parchment paper. This prevents sticking and ensures easy release—a crucial step for layer cakes.

Step 2: Mix Dry Ingredients In a large bowl, whisk together flour, sugar, cocoa powder, baking soda, baking powder, and salt until thoroughly combined. Sifting the cocoa prevents lumps and ensures even chocolate distribution throughout your best chocolate mayonnaise cake recipe.

Step 3: Combine Wet Ingredients In a separate bowl, whisk mayonnaise, warm water, and vanilla extract until smooth. The mayo should completely incorporate—don't worry if it looks unusual at first; it will blend beautifully.

Step 4: Create the Batter Pour the wet ingredients into the dry mixture and stir gently with a spatula until just combined. Do not overmix; a few small lumps are fine. Overmixing develops gluten, resulting in a tough cake instead of the tender texture this chocolate mayo cake is famous for.

Step 5: Bake Divide batter evenly between prepared pans. Bake for 28-32 minutes, or until a toothpick inserted in the center comes out with just a few moist crumbs. The tops should spring back when lightly touched.

Step 6: Cool Completely Let cakes cool in pans for 10 minutes, then invert onto wire racks. Cool completely before frosting—warm cake will melt your frosting and create a messy appearance.

Step 7: Make Frosting Beat softened butter until fluffy. Add cocoa powder and mix well. Gradually add powdered sugar alternating with milk, beating until smooth and spreadable. Add vanilla and optional espresso powder for enhanced chocolate flavor.

Step 8: Assemble Place one cake layer on your serving plate, spread frosting evenly, top with second layer, then frost top and sides generously.

Nutritional Information

Nutritional Information

Per serving (serves 12):

    • Calories: 425
    • Protein: 4g
    • Carbohydrates: 62g
    • Fat: 19g
    • Fiber: 3g
    • Iron: 12% DV
    • Calcium: 6% DV

Tips, Variations, or Cooking Advice

Dietary Swaps: Use vegan mayonnaise and plant-based milk for a completely dairy-free version. For gluten-free needs, substitute with a 1:1 gluten-free flour blend and add ½ teaspoon xanthan gum if your blend doesn't contain it.

Flavor Variations: Add ½ cup mini chocolate chips for extra indulgence, or fold in 1 teaspoon instant coffee granules to enhance chocolate depth. Try adding ½ teaspoon cinnamon for Mexican chocolate flavor.

Single Layer Option: Bake in a 9x13-inch pan for 35-40 minutes if you prefer sheet cake format—perfect for potlucks and easier storage.

Cupcake Conversion: This batter makes approximately 24 cupcakes; bake at 350°F for 18-22 minutes.

Common Mistakes to Avoid

Using Cold Mayo: Room temperature mayonnaise blends much more smoothly into the batter. Cold mayo creates lumps and doesn't emulsify properly with other ingredients.

Overbaking: This cake continues cooking from residual heat after removal from the oven. Pull it when the toothpick has moist crumbs, not when completely clean, to prevent dryness.

Skipping Parchment Paper: Even greased pans can stick. Parchment ensures your layers release perfectly without crumbling edges.

Frosting Too Soon: Patience is critical. Frosting a warm cake causes melting, sliding, and a complete mess. Always wait until layers are completely cool to touch.

Wrong Cocoa Type: Use unsweetened cocoa powder only. Dutch-processed works, but natural cocoa provides better rise with the baking soda in this recipe.

Storage / Leftovers Tips

Store this best chocolate mayonnaise cake covered at room temperature for up to 3 days, or refrigerate for up to one week in an airtight container. The mayonnaise acts as a preservative, keeping the cake incredibly moist even after several days—unlike traditional cakes that dry out quickly.

For longer storage, wrap unfrosted layers tightly in plastic wrap, then aluminum foil, and freeze for up to 3 months. Thaw overnight in the refrigerator before frosting. Frosted cake slices can be frozen individually wrapped for quick single servings; thaw at room temperature for 2-3 hours.

Refrigerated cake should sit at room temperature for 30 minutes before serving for the best texture and flavor. The chocolate mayo cake actually tastes even better on day two as flavors meld and moisture distributes throughout. Store in a cake dome or cover with an inverted bowl to prevent frosting from absorbing refrigerator odors.