White Chocolate Mousse Cake

White Chocolate Mousse Cake is the ultimate dessert for anyone who loves a combination of soft, fluffy cake and rich, velvety mousse. Starting with a white cake mix and elevating it with a few extra ingredients, this cake becomes something truly special. Topped with a homemade white chocolate mousse, stabilized with cream cheese, every bite is bursting with flavor.

No complicated steps here—just simple techniques that deliver big results. The cream cheese not only stabilizes the mousse but enhances the white chocolate flavor to a heavenly level. It's like biting into a fluffy cloud of sweetness! Perfect for holidays, special occasions, or a cozy baking night, this cake will impress every time.

Love cake and mousse? Check out my chocolate mousse cake, caramel mousse cake, chocolate cake with chocolate cream cheese frosting, chocolate mascarpone mousse, and chocolate orange cake with ganache.

Why you'll love this recipe

• Flavor: Every bite is packed with rich white chocolate flavor, balanced perfectly by the cream cheese’s slight tang. It’s sweet, creamy, and completely irresistible. You’ll find yourself going back for seconds.
• Ease: Using a box cake mix as a base saves time without sacrificing quality. The mousse comes together effortlessly thanks to cream cheese, which means no tricky gelatin or complicated steps. It's baking made easy but still feels gourmet.
• Dreamy Texture: The cake is soft and fluffy, while the mousse is light, creamy, and melts in your mouth. It’s like eating a cloud that’s been dipped in white chocolate.
• Versatility: Whether it’s a birthday, a holiday gathering, or just a random Tuesday when you feel like baking, this cake fits any occasion. Dress it up with decorations or keep it simple—it’s always a crowd-pleaser.

Equipment

Using a hand mixer or stand mixer is the best option when whipping cream because it saves both time and effort while ensuring the perfect texture. Whipping cream by hand with a whisk can be incredibly tedious—it takes a lot of strength and stamina to get it to the right consistency, and you could be whisking for what feels like forever.

A hand mixer or stand mixer does the hard work for you, creating soft or stiff peaks in just a few minutes. It also helps you achieve a more even and consistent result, which is especially important for recipes like mousse, where the texture needs to be light and fluffy.

Ingredients

Ingredients needed for white chocolate cake!

• White cake mix: Pick a high-quality mix, and don’t be afraid to experiment with one that includes real vanilla for an extra flavor boost.
• Sour cream: This is your secret weapon for a super moist cake. It adds richness and just a touch of tang to balance out the sweetness.
• High-quality white chocolate: Whether you’re melting it for the ganache or mixing it into the mousse, better chocolate equals better flavor. Look for brands with real cocoa butter for the best results.
• Heavy cream: Essential for making the ganache silky smooth and for whipping into that light, dreamy mousse texture.
• Full-fat brick-style cream cheese: Don’t skimp on the cream cheese! The full-fat kind is what gives the mousse structure and a creamy, tangy richness.

See recipe card for quantities.

Substitutions

Variations for the mousse cake!

• Serve with raspberry sauce: The tartness of raspberry sauce perfectly complements the sweetness of the white chocolate. Drizzle it on each slice or serve it on the side for an elegant touch.
• Make a layer cake: Bake the cake in round pans and layer it with mousse in between for a show-stopping presentation.
• Add sliced almonds: Sprinkle sliced almonds on top of the mousse or around the sides for a bit of crunch. For an even nuttier flavor, increase the almond extract in the cake batter.
• Mix in citrus zest: Add a teaspoon of lemon or orange zest to the mousse for a bright, zippy contrast to the rich white chocolate.
• Top with fresh berries: Garnish the cake with fresh raspberries, strawberries, or blueberries for a pop of color and natural sweetness.

This white chocolate mousse cake recipe has not been tested with other substitutions. These are just suggestions.

Instructions

Let's make white chocolate mousse cake recipe!

Step 1. Preheat the oven to 350°F. Line a 9X13 metal baking pan with parchment paper. Place all of the cake ingredients in a large bowl, beat until combined and smooth. Beat for 2 minutes, making sure to scrape the bottom of the bowl. Pour the batter into the cake pan, smoothing it out evenly.

Step 2. Chop the white chocolate finely and place it in a heatproof bowl. Heat the ½ cup of heavy cream in a small saucepan over medium heat until it just begins to simmer (do not boil). Pour the hot cream over the chopped white chocolate.

Step 3. Let the mixture sit undisturbed for 2-3 minutes to allow the chocolate to melt. Stir gently until smooth and fully combined. If it is not fully smooth and melted, microwave for 15 seconds at a time, stirring in between until smooth. Set the ganache aside to cool.

Step 4. Using a stand mixer or hand mixer In a large mixing bowl, beat the cream cheese until smooth and creamy. Add the cooled ganache and vanilla extract to the cream cheese. Beat the mixture until fully combined and smooth. Set aside. In a separate bowl, beat 1 ½ cups of heavy cream and powdered sugar. Continue whipping until stiff peaks form (when the cream holds its shape and doesn’t collapse).

Step 5. Gently fold the whipped cream into the cream cheese and ganache mixture. Use a spatula to fold carefully, ensuring you do not deflate the whipped cream. Mix until fully combined and smooth.
Make sure the cake is cool. Pour the mousse on top of the cake, spreading it out evenly.

Step 6. Refrigerate until cold and set, about 6 hours or overnight. Take the cake out for 45 minutes before serving, the cake should have time to get the chill out resulting in a fluffier cake.

Hint: When folding, go around the sides of the bowl swooping down the center, making sure to have a light hand so you don't knock down the air in the whipped cream.

Pro tips

• Make the ganache first: The ganache needs time to cool down before you use it in the mousse. If it’s too warm, it can mess with the texture, so getting this step out of the way early is key.
• Don’t overheat the cream: When you’re making the ganache, warm the cream just until it starts to steam—not boil. Overheating can cause the chocolate to seize or split, and no one wants to deal with that!
• Whip the heavy cream to stiff peaks: This step is important because stiff peaks help the mousse hold its shape and create that perfect light texture. Be careful not to under- or over-whip, or the mousse won’t be as stable.
• Avoid over mixing: When folding the whipped cream into the mousse, use a light hand. Over mixing can deflate the whipped cream, leaving you with a mousse that’s heavy instead of airy.
• Cool the cake completely: Patience pays off here! If the cake is even slightly warm, the mousse will start to melt, and things can get messy.
• Plan ahead: Make sure you give the mousse enough time to chill and set up in the fridge. This cake gets better with a little rest time, so don’t rush it.
• Use high-quality white chocolate: It might cost a little more, but trust me, it’s worth it. Good white chocolate melts better, tastes smoother, and makes all the difference in both the ganache and mousse for this white chocolate mousse cake.

FAQ

Storage

Refrigerator

White Chocolate Mousse Cake is best stored in the refrigerator to keep the mousse fresh and stable. Cover the cake tightly with plastic wrap or store it in an airtight container to prevent it from drying out or absorbing other flavors from the fridge. It will stay fresh for up to 3 days, though the texture of the mousse and cake is at its best on the first or second day.

Freezer

If you need to store the cake longer, it freezes beautifully. Place the cake on a tray and freeze uncovered for about an hour to set the mousse. Once firm, wrap it tightly in plastic wrap and then in aluminum foil to prevent freezer burn. Store it in the freezer for up to 1 month. To serve, thaw the cake in the refrigerator overnight for the best texture.

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📖 Recipe

White Chocolate Mousse Cake

Amanda Valsamis

This cake is the ultimate dessert for anyone who loves a combination of soft, fluffy cake and rich, velvety mousse. Starting with a white cake mix and elevating it with a few extra ingredients, this cake becomes something truly special. Topped with a homemade white chocolate mousse, stabilized with cream cheese, every bite is bursting with flavor.

5 from 1 vote

Print Recipe Pin Recipe

Prep Time 20 minutes mins

28 minutes mins

Total Time 48 minutes mins

Course Dessert

Cuisine American

Servings 16 slices

Equipment

• 9X13 metal baking pan metal is best!
• Parchment Paper
• Mixing bowls
• Measuring cups or kitchen scale
• Hand or stand mixer
• Measuring Spoons

Ingredients

  

Cake

• 1 box (14.5 oz, 400 grams) white cake mix or vanilla cake mix
• ½ cup (112 grams) granulated sugar
• ½ cup (66 grams) all purpose flour
• 1 cup (252 grams) whole milk 2% or buttermilk also works
• 1 cup (216 grams) sour cream full fat
• 4 large eggs
• 2 teaspoons vanilla extract
• ½ teaspoon almond extract gives bakery style flavor

White Chocolate Mousse

• 8 oz (227 grams) white chocolate high quality is best
• ½ cup (113 grams) heavy cream
• 8 oz (226 grams) cream cheese room temperature, full fat, brick style
• 1 ½ cups (330 grams) heavy cream cold
• ½ cup (62 grams) powdered sugar
• 1 teaspoon vanilla extract

Instructions

 

Cake

• Preheat the oven to 350°F. Line a 9X13 metal baking pan with parchment paper.
• Place all of the cake ingredients in a large bowl, beat until combined and smooth. Beat for 2 minutes, making sure to scrape the bottom of the bowl.
• Pour the batter into the pan, smoothing it out evenly.
• Place in the oven, bake for 26-28 minutes or until a toothpick inserted comes out clean.
• Set aside to cool.

White Chocolate Mousse

• Chop the white chocolate finely and place it in a heatproof bowl. Heat the ½ cup of heavy cream in a small saucepan over medium heat until it just begins to simmer (do not boil). Pour the hot cream over the chopped white chocolate.
• Let the mixture sit undisturbed for 2-3 minutes to allow the chocolate to melt. Stir gently until smooth and fully combined. If it is not fully smooth and melted, microwave for 15 seconds at a time, stirring in between until smooth. Set the ganache aside to cool.
• Using a stand mixer or hand mixer In a large mixing bowl, beat the cream cheese until smooth and creamy. Add the cooled ganache and vanilla extract to the cream cheese. Beat the mixture until fully combined and smooth. Set aside.
• In a separate bowl, beat 1 ½ cups of heavy cream and powdered sugar. Continue whipping until stiff peaks form (when the cream holds its shape and doesn’t collapse).
• Gently fold the whipped cream into the cream cheese and ganache mixture. Use a spatula to fold carefully, ensuring you do not deflate the whipped cream. Mix until fully combined and smooth.
• Make sure the cake is cool. Pour the mousse on top of the cake, spreading it out evenly. Cover and refrigerate until cold and set, about 6 hours or overnight. Take the cake out of the refrigerator for about 45 minutes before eating so the crumb has time to soften.
• See storage instructions in notes below.

Notes

Make the ganache first: The ganache needs time to cool down before you use it in the mousse. If it’s too warm, it can mess with the texture, so getting this step out of the way early is key.

Don’t overheat the cream: When you’re making the ganache, warm the cream just until it starts to steam—not boil. Overheating can cause the chocolate to seize or split, and no one wants to deal with that!

Whip the heavy cream to stiff peaks: This step is important because stiff peaks help the mousse hold its shape and create that perfect light texture. Be careful not to under- or over-whip, or the mousse won’t be as stable.

Avoid over mixing: When folding the whipped cream into the mousse, use a light hand. Over mixing can deflate the whipped cream, leaving you with a mousse that’s heavy instead of airy.

Cool the cake completely: Patience pays off here! If the cake is even slightly warm, the mousse will start to melt, and things can get messy.

Plan ahead: Make sure you give the mousse enough time to chill and set up in the fridge. This cake gets better with a little rest time, so don’t rush it.

Use high-quality white chocolate: It might cost a little more, but trust me, it’s worth it. Good white chocolate melts better, tastes smoother, and makes all the difference in both the ganache and mousse.

Storage

Refrigerator

White chocolate mousse cake is best stored in the refrigerator to keep the mousse fresh and stable. Cover the cake tightly with plastic wrap or store it in an airtight container to prevent it from drying out or absorbing other flavors from the fridge. It will stay fresh for up to 3 days, though the texture of the mousse and cake is at its best on the first or second day.

Freezer

If you need to store the cake longer, it freezes beautifully. Place the cake on a tray and freeze uncovered for about an hour to set the mousse. Once firm, wrap it tightly in plastic wrap and then in aluminum foil to prevent freezer burn. Store it in the freezer for up to 1 month. To serve, thaw the cake in the refrigerator overnight for the best texture.