Why You’ll Love Chocolate Mousse Cake Recipe

Rich Chocolate Flavor: The combination of dark chocolate cake and smooth mousse offers an intense chocolate experience.
Moist and Tender Cake: The cake’s texture is perfectly moist, complementing the airy mousse layer.
Impressive Presentation: This cake not only tastes amazing but also looks stunning, making it ideal for celebrations.

Ingredients

(Tip: You’ll find the full list of ingredients and measurements in the recipe card below.)

For the Cake:

All-purpose flour
Granulated sugar
Unsweetened cocoa powder
Baking soda
Baking powder
Salt
Buttermilk
Vegetable oil
Large eggs
Vanilla extract
Hot water

For the Chocolate Mousse:

Mini marshmallows
Semisweet baking chocolate
Milk
Heavy whipping cream
Vanilla extract

Directions

Prepare the Cake:

Preheat your oven to 350°F (175°C). Grease a 9×13-inch baking pan.
In a medium bowl, whisk together the flour, sugar, cocoa powder, baking soda, baking powder, and salt.
In a large bowl, combine the buttermilk and vegetable oil. Whisk in the eggs one at a time, then stir in the dry ingredients until just combined.
Add the hot water and vanilla extract, whisking until the batter is smooth.
Pour the batter into the prepared pan and bake for 30–35 minutes, or until a toothpick inserted into the center comes out clean. Allow the cake to cool completely.

Prepare the Chocolate Mousse:

In a large, heavy saucepan over low heat, combine the mini marshmallows, chopped semisweet chocolate, and milk. Stir continuously until melted and well combined. Remove from heat and let the mixture cool completely.
In a separate bowl, beat the heavy whipping cream and vanilla extract until soft peaks form.
Gently fold the cooled chocolate mixture into the whipped cream until fully incorporated.

Assemble the Cake:

Spread the chocolate mousse evenly over the cooled cake.
Refrigerate the assembled cake for at least 30 minutes to set the mousse before serving.

Servings and Timing

Servings: Approximately 20 servings
Preparation Time: 50 minutes
Cooking Time: 30 minutes

Variations

Alternative Toppings: Top the mousse with chocolate shavings, fresh berries, or a dusting of cocoa powder for added flair.
Different Chocolate: For a sweeter mousse, use milk chocolate instead of semisweet.
Layered Cake: Bake the cake in two round pans and layer with mousse between for a layered dessert.

Storage/Reheating

Storage: Cover and refrigerate the cake for up to 5 days.
Freezing: Freeze the cake without the mousse topping. Wrap the cooled cake tightly in plastic wrap and aluminum foil; it can be frozen for up to 1 month. Thaw in the refrigerator before adding the mousse.

FAQs

Can I use Dutch-processed cocoa powder for the cake?

The recipe recommends using regular unsweetened cocoa powder. Using Dutch-processed cocoa may alter the cake’s texture and rise due to differences in acidity.

What can I use as a substitute for buttermilk?

If you don’t have buttermilk, you can make a substitute by adding 1 tablespoon of lemon juice or white vinegar to a cup of milk and letting it sit for 5–10 minutes.

Is the mousse overly sweet because of the marshmallows?

No, the marshmallows help achieve a light and fluffy texture without making the mousse overly sweet.

Can I make this cake ahead of time?

Yes, the cake can be made a day in advance and stored in the refrigerator until ready to serve.

How do I know when the cake is done baking?

The cake is done when a toothpick inserted into the center comes out clean or with a few moist crumbs attached.

Can I use a different size pan?

This recipe is designed for a 9×13-inch pan. Using a different size may require adjusting baking times and could affect the outcome.

Is it necessary to refrigerate the cake after adding the mousse?

Yes, refrigerating helps set the mousse and makes the cake easier to slice and serve.

Can I add flavorings to the mousse?

Certainly! Adding a teaspoon of instant coffee or a splash of liqueur can enhance the chocolate flavor.

What type of chocolate is best for the mousse?

Semisweet baking chocolate is recommended, but you can adjust according to your sweetness preference.

Can I make the mousse without marshmallows?

Marshmallows help provide structure and sweetness. If avoiding them, you can try a traditional mousse with egg yolks or gelatin, though it will change the texture.

Conclusion

Chocolate Mousse Cake is a show-stopping dessert that’s as delicious as it is beautiful. With a rich chocolate base and a light, fluffy mousse topping, it’s perfect for entertaining or treating yourself. Its layered textures and deep chocolate flavor are sure to impress anyone lucky enough to get a slice.

Chocolate Mousse Cake

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Indulge in the ultimate chocolate lover’s dream with this Chocolate Mousse Cake. Featuring a moist, rich dark chocolate cake base and a creamy, dreamy chocolate mousse topping, this dessert is elegant, irresistible, and perfect for special occasions or a decadent treat anytime.

Author: Emily
Prep Time: 50 minutes
Cook Time: 30 minutes
Total Time: 1 hour 20 minutes
Yield: 20 servings
Category: Dessert
Method: Baking
Cuisine: American
Diet: Vegetarian

Instructions

Prepare the Cake:
Preheat oven to 350°F (175°C). Grease a 9×13-inch metal baking pan.
In a medium bowl, whisk together flour, sugar, cocoa powder, baking soda, baking powder, and salt.
In a large bowl, whisk together buttermilk and vegetable oil.
Add eggs one at a time, whisking well after each.
Gradually stir in the dry ingredients until just combined.
Add hot water and vanilla extract, whisking until smooth.
Pour batter into prepared pan and bake for 30–40 minutes, or until a toothpick comes out clean.
Let the cake cool completely.
Prepare the Chocolate Mousse:
In a saucepan, combine mini marshmallows, chopped chocolate, and milk.
Cook over low heat, stirring constantly, until smooth. Let cool completely.
In a separate bowl, beat cold heavy cream with vanilla extract until soft peaks form.
Fold whipped cream gently into the cooled chocolate mixture.
Assemble the Cake:
Spread the chocolate mousse evenly over the cooled cake.
Refrigerate for at least 30 minutes before serving.

Notes

Use milk chocolate instead of semisweet for a sweeter mousse.
No buttermilk? Mix 1 cup milk with 1 tbsp lemon juice or vinegar, let sit 5–10 minutes.
Store leftovers covered in the fridge for up to 5 days.