Name: Chocolate Mousse Cake
Prep time: 30 min
Cook time: 30 min
Total time: 5 h
Cuisine: French
Ingredients: 1 cup all-purpose flour; 1/2 cup cocoa powder; 1 tsp baking powder; 1/2 tsp baking soda; 1 cup sugar; 2 eggs; 1/2 cup milk; 1/2 cup vegetable oil; 1 tsp vanilla extract; 1/2 cup boiling water; 8 oz semi-sweet or dark chocolate; 2 cups heavy cream; 1 tbsp unflavored gelatin (optional); 2 tbsp water (for dissolving gelatin, optional)

Why You’ll Love This Recipe

This chocolate mousse cake strikes the perfect balance between indulgent and light. The mousse layer adds a creamy texture that complements the dense cake base without being overly sweet. It’s a showstopping dessert that’s surprisingly easy to make, and it can be prepared ahead of time, making it ideal for dinner parties or celebrations. Plus, you only need a few basic ingredients to create something truly memorable.

Ingredients

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

All-purpose flour
Cocoa powder
Baking powder
Baking soda
Sugar
Eggs
Milk
Vegetable oil
Vanilla extract
Boiling water
Semi-sweet or dark chocolate
Heavy cream
Gelatin (optional, for extra stability)

Directions

Make the cake base: Preheat your oven to 350°F (175°C). Grease and line a round cake pan. In a large bowl, mix flour, cocoa powder, baking powder, baking soda, and sugar. Add eggs, milk, oil, and vanilla. Mix until smooth. Stir in boiling water last (batter will be thin). Pour into the prepared pan and bake for 25–30 minutes. Let cool completely.
Make the chocolate mousse: Melt the chocolate in a heatproof bowl over simmering water or in the microwave. Let it cool slightly. Whip the heavy cream until stiff peaks form. Fold the melted chocolate into the whipped cream gently until fully combined. If using gelatin, dissolve it in warm water and mix it in to stabilize the mousse.
Assemble: Place the cooled cake layer into a springform pan or cake ring. Pour the mousse over the cake layer and smooth the top. Refrigerate for at least 4 hours or until set.
Serve: Carefully remove the cake from the pan. Garnish with chocolate shavings, cocoa powder, or fresh berries if desired. Slice and serve chilled.

Servings and timing

This chocolate mousse cake serves 10–12 people. Prep time is about 30 minutes, bake time is 25–30 minutes, and chill time is at least 4 hours (preferably overnight).

Variations

White Chocolate Mousse: Swap dark chocolate for white chocolate for a lighter twist.
Coffee-Infused: Add 1–2 teaspoons of instant espresso to the mousse for a mocha flavor.
Fruit Layer: Add a layer of raspberries or strawberries between the cake and mousse.
Nutty Crunch: Sprinkle crushed hazelnuts or almonds over the cake before adding the mousse.
No-Bake Base: Use a cookie crumb base instead of a baked cake for a quicker version.

Storage/Reheating

Store the chocolate mousse cake in the refrigerator, covered, for up to 4 days. For best texture, serve it chilled. Freezing is possible, but the mousse texture may slightly change—if freezing, wrap tightly and consume within 1 month. Thaw in the refrigerator overnight. This cake does not require reheating.

FAQs

Can I make this cake in advance?

Yes, this cake is perfect for making a day ahead. The mousse needs time to set, so chilling overnight is ideal.

Does the mousse need gelatin?

No, but gelatin helps the mousse hold its shape better, especially if the cake will sit out for a while.

Can I use milk chocolate instead of dark chocolate?

Yes, but it will result in a much sweeter mousse. Adjust sugar levels if needed.

How do I make the cake gluten-free?

Use a gluten-free flour blend in place of regular flour. Make sure all other ingredients are gluten-free.

Can I freeze chocolate mousse cake?

Yes, freeze the fully assembled cake for up to 1 month. Thaw in the fridge before serving.

How can I make a no-bake version?

Use a cookie crust (like crushed Oreos or graham crackers with butter) instead of baking a cake base.

What kind of chocolate should I use for the mousse?

High-quality semi-sweet or dark chocolate is best for a rich flavor and smooth texture.

Can I use whipped topping instead of heavy cream?

You can, but real whipped cream gives a better texture and flavor to the mousse.

How do I get smooth mousse?

Melt the chocolate slowly and fold it gently into the whipped cream to keep it light and airy.

Can I add flavorings to the mousse?

Yes, try adding a splash of liqueur like Baileys, Kahlúa, or a few drops of peppermint extract.

Conclusion

Chocolate mousse cake is a luxurious dessert that looks impressive and tastes divine. With a rich cake base and a silky mousse topping, it’s a crowd-pleaser that’s perfect for birthdays, holidays, or whenever you’re craving a chocolatey indulgence. Simple to make and easy to customize, this dessert is one you’ll come back to again and again.