This Chocolate Mousse Cake is a true comfort-food favorite with a refined, lighter feel. A moist cocoa sponge supports a silky, airy chocolate mousse, finished with smooth ganache for a bakery-style result at home. Sophie tested this recipe more than nine times to perfect the balance of richness and lightness, making it ideal for home cooks serving family gatherings or special occasions. The use of whipped cream and folded egg whites keeps the texture airy while delivering deep chocolate flavor that American dessert lovers expect.
Prep Time: 40 min | Cook Time: 35 min | Total Time: 1 hr 15 min (plus chilling)
Key Ingredients
- Cocoa powder (25 g)
- Instant coffee (½ tsp, enhances chocolate flavor)
- Vegetable oil (100 ml)
- Buttermilk (60 ml, or milk with lemon juice)
- Eggs (2 whole + 4 whites + 4 yolks)
- Plain flour (100 g)
- Granulated sugar (110 g total)
- Light brown sugar (60 g)
- Dark chocolate (200 g)
- Milk chocolate (400 g total)
- Double cream (420 ml total)
- Vanilla extract, cream of tartar, baking soda, white vinegar, salt
Step-by-Step Instructions
Preheat the oven to 180°C / 350°F and line an 8-inch cake tin. Whisk cocoa powder, instant coffee, and hot water until smooth, then mix in oil, buttermilk, and eggs. Add flour and sugars, mixing just until combined. Activate baking soda with vinegar and whisk into the batter. Bake for 30–35 minutes until a toothpick comes out clean, then cool completely.
For the mousse, whip the cream to firm peaks and chill. Whip egg whites with cream of tartar, gradually adding sugar until stiff peaks form. Melt dark and milk chocolate, then whisk in egg yolks, vanilla, and salt. Lighten with a spoon of whipped cream, fold in remaining cream, then gently fold in egg whites in two additions.
Place the cooled cake layer into a lined springform pan, add mousse, smooth the top, and freeze for 20 minutes. Melt milk chocolate and cream to make ganache, pour over the chilled mousse, smooth, and refrigerate overnight. Decorate as desired and slice to serve.
Serving Suggestions
Serve with fresh berries, a dusting of cocoa powder, lightly sweetened whipped cream, or alongside espresso or coffee.
Storage & Make-Ahead Tips
Store covered in the refrigerator for up to four days. Freeze individual slices for up to one month and thaw overnight. The entire cake can be prepared a day ahead for stress-free entertaining.
Tips & Tricks
Use room-temperature eggs for smoother emulsions. Fold gently to maintain mousse volume. Chill fully before slicing for clean layers.
Common Mistakes to Avoid
Overmixing the mousse, pouring ganache on warm mousse, or skipping the overnight chill.
Chef’s Advice
Swap part of the milk chocolate for semi-sweet if you prefer less sweetness. Add espresso powder or orange zest for flavor variation. For cookie lovers, explore stuffed dessert ideas like Stuffed Red Velvet Cookies, Peanut Butter Nutella Cookies, or White Chocolate Stuffed Cookies available on sweetcraftrecipes.com.
History and Cultural Significance
Chocolate mousse dates back to 18th-century France and evolved into layered mousse cakes that became popular in American bakeries for their elegant texture contrasts and rich chocolate appeal.
Final Thoughts
This Chocolate Mousse Cake combines classic American dessert comfort with a lighter, modern approach. Carefully tested and family-approved, it delivers impressive results with approachable techniques that home cooks can trust.
Nutrition Information
| Serving Size | Calories | Protein | Carbs | Fat | Fiber | Sugar |
|---|---|---|---|---|---|---|
| 1 serving | ~420 kcal | 6 g | 38 g | 28 g | 3 g | 26 g |
Disclaimer: Nutrition information is estimated using standard online calculation tools and may vary based on ingredients and preparation methods. For accurate dietary advice, consult a qualified nutrition professional.
PrintChocolate Mousse Cake
Rich, creamy chocolate mousse cake with a lighter twist. A moist cocoa sponge layered with airy chocolate mousse and finished with silky ganache. Elegant, indulgent, and perfectly balanced for special occasions or family gatherings.
- Prep Time: 40 minutes
- Cook Time: 35 minutes
- Total Time: 1 hour 15 minutes
- Yield: 12 servings
- Category: Dessert
- Cuisine: American
Ingredients
**Chocolate Cake Layer**
25 g cocoa powder
1/2 tsp instant coffee
100 ml vegetable oil
60 ml buttermilk (or milk with lemon juice)
2 whole eggs, room temperature
100 g all-purpose flour
60 g light brown sugar
50 g granulated sugar
1/2 tsp baking soda
1 tsp white vinegar
1/4 tsp salt
**Chocolate Mousse**
200 g dark chocolate
200 g milk chocolate
4 egg yolks
4 egg whites
1/4 tsp cream of tartar
60 g granulated sugar
300 ml double cream
1 tsp vanilla extract
Pinch of salt
**Chocolate Ganache**
200 g milk chocolate
120 ml double cream
Instructions
**Bake the Cake**
Preheat oven to 350°F (180°C). Line an 8-inch cake pan. Whisk cocoa powder, instant coffee, and hot water until smooth. Mix in oil, buttermilk, and eggs. Add flour and sugars and mix just until combined. Activate baking soda with vinegar and whisk into batter. Bake 30–35 minutes until a toothpick comes out clean. Cool completely.
**Prepare the Mousse**
Whip double cream to firm peaks and refrigerate. Whip egg whites with cream of tartar, gradually adding sugar until stiff peaks form. Melt dark and milk chocolate together. Whisk in egg yolks, vanilla, and salt. Lighten mixture with a spoon of whipped cream, then fold in remaining cream. Gently fold in egg whites in two additions.
**Assemble the Cake**
Place cooled cake in a lined springform pan. Spread mousse evenly over cake. Smooth top and freeze for 20 minutes.
**Make the Ganache**
Heat cream until steaming, pour over chopped milk chocolate, and stir until smooth. Pour ganache over chilled mousse and smooth the surface.
**Chill & Serve**
Refrigerate overnight. Slice with a warm knife for clean layers and serve chilled.
Notes
• Chill fully before slicing for sharp layers.
• Use room-temperature eggs for best emulsions.
• Fold gently to keep the mousse light and airy.
• Swap part of the milk chocolate for semi-sweet to reduce sweetness.
• Freeze individual slices for up to 1 month.
