Chocolate Cake with Chocolate Mousse
Updated May 04, 2025, Published Apr 18, 2025
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This Chocolate Cake with Chocolate Mousse is a chocolate lover’s dream! It features layers of moist chocolate cake with a shiny chocolate ganache filling and a rich chocolate mousse!
If you love this chocolate cake recipe, you’ll LOVE my triple chocolate cake, chocolate ricotta cake, and chocolate cake with chocolate cream cheese frosting too!
This triple chocolate mousse cake is one for the record books! You’re going to LOVE this recipe!
You’ve got two rich, fudgy chocolate cake layers doing the heavy lifting. Then there’s a thick, dreamy layer of a rich chocolate ganache that seals the deal. And just when you think it can’t get more decadent, it gets smothered in a fluffy chocolate mousse!
It’s basically a chocolate lover’s dream that said, “Go big or go home,” and then added an extra swirl for good measure.
This Chocolate Cake with Chocolate Mousse recipe is a bit of a labor of love. But I PROMISE it delivers every time. Ideal for any special occasion for the chocolate lover in your life. Happy baking!
Table of contents
Why this is the Best Chocolate Mousse Cake
- The soft chocolate cake with the velvety chocolate mousse make this cake melt in your mouth! It’s lusciously creamy and deeply chocolatey – I am SO in love with this cake!
- Because this recipe uses gelatin in the chocolate mousse, it’s stable at room temperature! This makes this cake ideal for holiday dinners, birthday parties, or any special occasion!
- Bakery style chocolate cake – but at home! I equip you with tips, tricks, and step-by-step instructions and photos so that anyone can make this cake – novice or pro!!
Key Ingredients
(full list of ingredients can be found in the recipe card)
- Cake flour makes this chocolate mousse cake recipe extra tender and soft. It has lower protein content than all purpose flour. This means less gluten and a finer crumb, giving you a beautifully soft texture.
- Unsweetened Cocoa Powder, not to be confused with dutch process cocoa powder, give the cake it’s deep, bold chocolate flavor.
- Hot Coffee enhances the chocolate flavor! It also helps dissolve the cocoa powder smoothly so your cake bakes up extra rich and moist. (don’t worry, the cake won’t taste like coffee!)
- Vegetable oil keeps chocolate cake super moist and soft, while melted butter brings that rich, buttery flavor and extra tenderness. Together, they’re basically the dream team for a cake that’s crazy moist and delicious.
- Sour cream makes chocolate cake insanely moist and gives it a slight tang that balances all the rich chocolate flavor.
- Vinegar reacts with baking soda to create bubbles that make the chocolate cake rise and stay fluffy. You can use white vinegar or apple cider vinegar.
- Gelatin helps chocolate mousse set up nice and firm without losing that light, airy texture. It’s basically the secret weapon for mousse that holds its shape but still feels silky and smooth. I also use this for my mango mousse recipe, try that next!
- Semi-Sweet Chocolate Chips add chocolate flavor and sweetness to both the ganache and the mousse. It also helps the mousse to set. You can use chocolate bars if you prefer them over chips!
- Heavy Cream is used in both the chocolate ganache and chocolate mousse filling. For the ganache, heavy cream melts into the chocolate to make it glossy, smooth, and perfectly spreadable. In the chocolate mousse, heavy cream adds that soft, airy, melt-in-your-mouth texture!
- Egg yolks make chocolate mousse extra rich and silky by adding fat and helping create that smooth, creamy texture. Save the egg whites and make my strawberry cake with strawberry filling!
Substitutions
- If you don’t have any coffee handy, use hot water and espresso powder for a quick and easy substitute. If you don’t have espresso powder, hot water will do just fine!
- Gelatin can be found at most grocery stores. If you don’t have any or simply can’t find it, you can make the mousse recipe without it. However, it won’t be as stable at room temperature so place it back into the refrigerator after serving.
- For a less sweet cake, use a high quality dark chocolate instead.
How to make Chocolate Mousse Cake
Prepare the Creamy Chocolate Mousse
Step 1: Begin by making the chocolate mousse. Add gelatin and cold water to a small bowl or cup and gently mix together. Set aside while making the mousse. Add egg yolks, 1 cup of heavy cream, and sugar to a medium saucepan. Use a hand mixer to mix everything together for about 2-3 minutes, until bubbly/frothy. Place the pan on the stove over medium heat, stirring frequently for about 5-7 minutes, until slightly thickened.
Step 2: Add in the semi-sweet chocolate chips and allow it to sit for about 1-2 minutes, then stir together until all of the chocolate is fully melted into the cream mixture. Add the gelatin and continue to stir until the gelatin is fully dissolved and the mixture is smooth, about 2-3 minutes. Remove from the heat and set aside.
Step 3: In a separate large bowl, use a hand mixer to beat the remaining 1 cup of heavy cream until stiff peaks form, about 5 minutes.
Step 4: Add the chocolate mixture to the whipped cream and continue to mix until combined (it may look soupy – this is normal). Cover with plastic wrap and place into the refrigerator to set for at least 3 hours.
Make the Chocolate Cake Layers
Preheat the oven to 350 degrees F. Spray 2 9-inch cake pans with nonstick baking spray or line with parchment paper. Set aside.
Step 5: In a large mixing bowl, whisk together vegetable oil, melted butter, sugar, sour cream, and vanilla extract until combined and smooth, about 1-2 minutes. Add in the eggs and vinegar and continue to mix until combined, about 30 seconds.
Step 6: To the same bowl, add cake flour, unsweetened cocoa powder, baking soda, and kosher salt.
Step 7: Gently fold together until a smooth batter forms, about 1 minute, then pour hot coffee on top. Let the coffee sit for about 30 seconds, then whisk together until a smooth batter comes together, about 30 seconds.
Divide the cake batter equally amongst two the cake pans and bake for 30-35 minutes, until a wooden skewer comes out with just a few crumbs. Allow the cakes to cool in the pan for 10 minutes, then turn over onto a wire rack to cool completely.
Make the Chocolate Ganache
Step 8: Add heavy whipping cream to a heat-proof bowl and warm in the microwave for about 1 minute, until hot. Add chocolate chips and let it sit for 2 minutes. Stir together until the chocolate is fully melted into the cream (if it’s not fully melted, place back into the microwave in 15 seconds increments, stirring between each time). Once fully melted, add butter and stir until the butter is melted into the chocolate. Set aside to cool and set.
Assemble the Cake
Step 9: Line a springform pan with parchment paper on the bottom and on the sides, making sure to have about 2 inches overhang OR use a acetate cake collar. Place the one of the cooled cakes on bottom of the springform pan. Add a thin layer of the chocolate ganache and smooth into an even layer.
Step 10: Remove the chocolate mousse from the refrigerator and add half of the mousse on top of the chocolate ganache.
Step 11: Gently place the second cake layer on top of the mousse and smooth the remaining ganache on top, then add remaining chocolate mousse on top of the ganache. Place back into the refrigerator to set for about 4-6 hours. When you’re ready to serve, remove from the springform pan and peel off the parchment paper (or cake collar if using). Garnish with chopped chocolate or chocolate curls.
Expert Baking Tips
- Chill thoroughly before serving: Let the finished cake set in the fridge for at least 4–6 hours (preferably overnight) so the mousse firms up and slices cleanly
- Warm your knife to get clean cut slices: Dip a sharp knife in hot water and wipe it dry between slices for those clean, bakery-style cuts.
- Make sure everything is at the right temperature: Make sure that the cakes have cooled completely prior to assembling the cake! This is crucial or else the mousse will melt! In addition, make sure that the chocolate mousse is set prior to adding to the cake or else it can seep into the cake and make it too mushy.
- Use a springform pan or cake ring to assemble the cake: Line the sides of the springform pan with acetate or parchment for super smooth edges when you unmold the cake.
- Use good quality chocolate: The flavor of your mousse depends entirely on the chocolate you use. Pick a high quality semi-sweet chocolate (at least 60% cacao) or dark chocolate per your preference.
Recipe FAQs
Due to the gelatin in the mousse, this recipe is VERY stable and is able to sit at room temperature for several hours. If the mousse is melting, it’s because the cake was still hot and was assembled before everything was completely cooled.
You can! The cake freezes well, just be sure to freeze the actual cake layers and not the finished cake. Once the baked cake has cooled to room temperature, wrap it tightly in plastic wrap and then wrap it in aluminum foil. The cake will keep for up to 1 month in the freezer. Make the chocolate mousse and chocolate ganache once you’re ready to serve, assemble, and let the cake set in the fridge prior to serving.
You should keep the chocolate mousse cake in an airtight container in the fridge for up to a week. If freezing, wrap the cake tightly let it defrost in the fridge for 30–60 minutes before eating
The chocolate mousse will be runny prior to setting in the fridge – this is completely normal. As the mousse cools, it will set up and be fully fluffy and stable and ready to use!
More Chocolate Cake Recipes
Desserts
Chocolate Donut Cake
Desserts
White Chocolate Pound Cake
Desserts
Chocolate Pudding Cake
Desserts
Matilda’s Chocolate Cake
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If you make this recipe, please leave a star rating on the recipe card and comment below! You can also tag @BritneyBreaksBread on Instagram and hashtag #britneybreaksbread so I can celebrate your beautiful creations!
Chocolate Cake with Chocolate Mousse
Equipment
- 2 9 inch cake pans
- Mixing Bowls
- Medium Saucepan
- Cake Collar (optional)
Ingredients
Chocolate Mousse
- 1 tsp Gelatin
- 1 tbsp Cold Water
- 4 Large (72 g) Egg Yolks
- 2 cups (480 ml) Heavy Cream, (divided)
- 1/2 cup Sugar
- 2 1/4 cups (405 g) Semi-Sweet Chocolate Chips
Chocolate Cake
- 2 cups (250 g) Cake Flour
- 3/4 cups (65 g) Unsweetened Cocoa Powder
- 2 tsp Baking Soda
- 1 tsp Kosher Salt
- 3/4 cup + 1 tbsp (182 g) Vegetable Oil
- 5 tbsps (70 g) Salted Butter, (melted)
- 2 1/2 cups (500 g) Sugar
- 1 cup Sour Cream, (room temperature)
- 2 Large (100 g) Eggs, (room temperature)
- 1 (18 g) Egg Yolk, (room temperature)
- 1 tbsp Vanilla Extract
- 2 tbsp Vinegar
- 1 1/2 cups (360 g) Coffee, (hot)
Chocolate Ganache
- 1 1/2 cups (270 g) Semi-Sweet Chocolate Chips
- 3/4 cup (180 ml) Heavy Cream
- 3 tbsps Salted Butter
Instructions
Prepare the Creamy Chocolate Mousse
- Begin by making the chocolate mousse. Add gelatin and cold water to a small bowl or cup and gently mix together. Set aside while making the mousse. Add egg yolks, 1 cup of heavy cream, and sugar to a medium saucepan. Use a hand mixer to mix everything together for about 2-3 minutes, until bubbly/frothy. Place the pan on the stove over medium heat, stirring frequently for about 5-7 minutes, until slightly thickened. 1 tsp Gelatin 1 tbsp Cold Water 4 Large Egg Yolks 1/2 cup Sugar
- Add in the semi-sweet chocolate chips and allow it to sit for about 1-2 minutes, then stir together until all of the chocolate is fully melted into the cream mixture. Add the gelatin and continue to stir until the gelatin is fully dissolved and the mixture is smooth, about 2-3 minutes. Remove from the heat and set aside. 2 1/4 cups Semi-Sweet Chocolate Chips
- In a separate large bowl, use a hand mixer to beat the remaining 1 cup of heavy cream until stiff peaks form, about 5 minutes. Add the chocolate mixture to the whipped cream and continue to mix until combined (it may look soupy – this is normal). Cover with plastic wrap and place into the refrigerator to set for at least 3 hours.
Make the Chocolate Cake Layers
- Preheat the oven to 350 degrees F. Spray 2 9-inch cake pans with nonstick baking spray or line with parchment paper. Set aside.
- In a large mixing bowl, whisk together vegetable oil, melted butter, sugar, sour cream, and vanilla extract until combined and smooth, about 1-2 minutes. Add in the eggs, egg yolk, and vinegar and continue to mix until combined, about 30 seconds. 3/4 cup + 1 tbsp Vegetable Oil 5 tbsps Salted Butter 2 1/2 cups Sugar 1 cup Sour Cream 1 tbsp Vanilla Extract 2 Large Eggs 1 Egg Yolk 2 tbsp Vinegar
- To the same bowl, add cake flour, unsweetened cocoa powder, baking soda, and kosher salt. Gently fold together until a smooth batter forms, about 1 minute, then pour hot coffee on top. Let the coffee sit for about 30 seconds, then whisk together until a smooth batter comes together, about 30 seconds. 2 cups Cake Flour 3/4 cups Unsweetened Cocoa Powder 2 tsp Baking Soda 1 tsp Kosher Salt 1 1/2 cups Coffee
- Divide the cake batter equally amongst two the cake pans and bake for 30-35 minutes, until a wooden skewer comes out with just a few crumbs. Allow the cakes to cool in the pan for 10 minutes, then turn over onto a wire rack to cool completely.
Make the Chocolate Ganache
- Add 3/4 heavy whipping cream to a heat-proof bowl and warm in the microwave for about 1 minute, until hot. Add chocolate chips and let it sit for 2 minutes. Stir together until the chocolate is fully melted into the cream (if it's not fully melted, place back into the microwave in 15 seconds increments, stirring between each time). 3/4 cup Heavy Cream 1 1/2 cups Semi-Sweet Chocolate Chips
- Once fully melted, add butter and stir until the butter is melted into the chocolate. Set aside to cool and set. 3 tbsps Salted Butter
Assemble the Cake
- Line a springform pan with parchment paper on the bottom and on the sides, making sure to have about 2 inches overhang OR use a acetate cake collar.
- Place the one of the cooled cakes on bottom of the springform pan. Add a thin layer of the chocolate ganache and smooth into an even layer. Remove the chocolate mousse from the refrigerator and add half of the mousse on top of the chocolate ganache.
- Gently place the second cake layer on top of the mousse and smooth the remaining ganache on top, then add remaining chocolate mousse on top of the ganache. Place back into the refrigerator to set for about 4-6 hours. When you're ready to serve, remove from the springform pan and peel off the parchment paper (or cake collar if using). Garnish with chopped chocolate or chocolate curls.
Notes
- Chill thoroughly before serving: Let the finished cake set in the fridge for at least 4–6 hours (preferably overnight) so the mousse firms up and slices cleanly
- Warm your knife to get clean cut slices: Dip a sharp knife in hot water and wipe it dry between slices for those clean, bakery-style cuts.
- Make sure everything is at the right temperature: Make sure that the cakes have cooled completely prior to assembling the cake! This is crucial or else the mousse will melt! In addition, make sure that the chocolate mousse is set prior to adding to the cake or else it can seep into the cake and make it too mushy.
- Use a springform pan or cake ring to assemble the cake: Line the sides of the springform pan with acetate or parchment for super smooth edges when you unmold the cake.
- Use good quality chocolate: The flavor of your mousse depends entirely on the chocolate you use. Pick a high quality semi-sweet chocolate (at least 60% cacao) or dark chocolate per your preference.
Nutrition
Nutrition information is automatically calculated, so should only be used as an approximation.
Loved eating this cake! It was finger licking good and my family loved every last piece!
Yay! So glad it was a home run!
I don’t really like chocolate cake because of it’s richness BUT this one changed my mind!!!! This recipe is amazing as the cake is moist, delicate, and surprisingly it’s not over powered with sweetness! You will not be disappointed, I highly recommend! 🙌🏾
Thank you so much! I’m so happy that you enjoyed it!