This chocolate raspberry mousse cake has the perfect balance of tart and sweet! Its moist chocolate cake layers are filled with fluffy chocolate mousse, tart raspberry jam, and are studded with fresh raspberries.

How to Make This Chocolate Raspberry Mousse Cake

To make sure your chocolate raspberry mousse cake turns out as amazing as possible, let’s walk through each step together! I’ve also included a video tutorial of the process below.

Step 1: Make the Chocolate Mousse

Make the chocolate mousse first, so it has time to chill.

Melt the chocolate chips by placing them in a medium-sized, heat-proof bowl. Heat in 20-30 second increments in the microwave, stirring after each increment until the chocolate completely melted and smooth. If you don’t have a microwave, you can also use a double boiler.

In a small bowl, whisk together the hot water and cocoa powder. Pour into the melted chocolate and whisk together until smooth. The mixture should be somewhat thick. Set aside.

Add the heavy cream, powdered sugar, vanilla extract, and a pinch of fine salt in a large bowl or the bowl of a stand mixer fit with a whisk attachment.

Mix on medium-high speed until the whipped cream starts to gather in the whisk attachment and you can see texture around the edges of the bowl (see photo below). At this stage the whipped cream should be thick and able to keep its shape. This usually takes about 2 1/2 to 3 minutes in my stand mixer.

Gently fold the chocolate mixture into the whipped cream using a rubber spatula.

Use the spatula to swoop around the sides of the bowl and pull through the center like I show in the video of this recipe. Be careful not to over-mix the mousse, or it will become deflated and lose its structure.

Be careful not to over-mix the mousse, or it will become deflated and lose its structure. Cover the mousse with plastic wrap and chill in the refrigerator for at least 2 hours.

Step 2: Bake and Level the Chocolate Cake Layers

Next, make the chocolate cake batter. Divide the batter evenly between the prepared 8-inch cake pans. Bake for 23-26 minutes or until a toothpick comes out with a few moist crumbs.

Remove the cake layers from the oven and let them cool in the pans for about 10 minutes. Gently run an offset spatula around the rim of the cake pans to loosen them, then flip them into wire racks to finish cooling.

Once the cake layers have cooled to room temperature, use a serrated knife to level the top of each cake layer. It makes the cake so much easier to stack and assemble!!

If you’re making these in advance, you can wrap and freeze them at this point.

Step 3: Make the Chocolate Buttercream

While the cake layers bake and cool, make the chocolate buttercream. This frosting can also be made in advance if needed and kept in the fridge for up to a month!

If your frosting seems too thick after mixing your ingredients, add in additional cream (1 tablespoon at a time). Or if the frosting is too thin, add in more powdered sugar (quarter of a cup at a time).

If you’re unsure how thick your frosting should be, you can learn what consistency you’re looking for in my frosting consistency post.

Step 4: Stack and Fill the Cake Layers

Stack and frost cake layers on a greaseproof cake board, using a dab of chocolate buttercream to help stick the first cake layer to the board.

As you assemble the cake, spread about 1/4 cup of raspberry jam on each cake layer. Spread about 1/3 of the chocolate mousse in an even layer on top of the jam.

If desired, gently press about 2/3 cup of fresh raspberries into the mousse.

Repeat with the remaining cake layers. Smooth any overhanging mousse around the cake with a large offset spatula, then freeze the cake for about 10 minutes in the freezer.

This will help the buttercream between the cake layers firm up and make the cake way easier to frost.

Step 5: Spread on a Thick Layer of Frosting

Cover the cake with a thick, even layer of chocolate buttercream and use an offset spatula or the back of a spoon to make some cute swoops around the cake.

This is an easy and stress-free way to decorate a cake that gives it a beautiful finished look. Top with a semicircle of fresh raspberries and enjoy!

Substitutions & Swaps: Chocolate Cake Layers

While I love this chocolate raspberry mousse cake just the way it is, I know some of you might not have all these ingredients on hand.

Below are some swaps and substitutions that can be made in this recipe:

• All Purpose Flour – This recipe turns out best with all purpose flour. However, you can swap in a good gluten free flour blend (like this) if needed. Just be sure to stir the batter longer than normal to help give the cake proper structure, and let the batter sit for about 20 minutes before baking it if you opt to make a gluten free version.
• Granulated Sugar – I do not recommend reducing the amount of sugar or changing the type of sugar, as it will change the texture of the cake layers.
• Dark Baking Cocoa – I like to use the Hershey’s brand of dark baking cocoa, but you can also use black cocoa. If you can’t find dark cocoa powder or don’t have any on hand, you can use regular unsweetened baking cocoa in its place.
• Buttermilk – You can also use full fat yogurt, sour cream, whole milk, or an alternative yogurt or milk (almond, soy, oat).
• Vegetable Oil – Use any flavorless oil can in this recipe. Canola, vegetable, or even sunflower oil would all work great. I don’t recommend olive oil though, as it has a strong flavor and will change the taste of the cake.
• Eggs – This recipe uses large eggs. If you have an egg allergy you can try using a vegan egg replacer.
• Raspberry Jam – Spread a jar of jam on top of each cake layer to pack it with fruity flavor! I like using seedless raspberry jam, but any jam will work! You can also use strawberry or blackberry jam instead of raspberry if needed. Just be sure to match the fruit you fill the cake with to the jam you use.
• Fresh Raspberries – I like to add fresh raspberries between the cake layers. This is optional, but I really think it adds to the texture and flavor of this cake. Alternatively, you can use strawberry slices or fresh blackberries if you can find fresh raspberries.

Substitutions & Swaps: Chocolate Buttercream

Some swaps and substitutions that can be made in this frosting recipe include:

• Unsalted Butter – If you only have salted butter, on hand you can use it in place of the unsalted butter. Just be sure to omit the salt that this frosting recipe calls for. You can also use vegan butter in its place!
• Dark Cocoa Powder – If you can’t find dark cocoa powder or don’t have any on hand, you can use regular unsweetened baking cocoa or add additional powdered sugar in its place.
• Heavy Cream – Whole milk or alternative milk (soy, almond, oat) can also be used to make the frosting.
• Dark Chocolate – You can use dark chocolate chips, baking chocolate, or good-quality chocolate bars to melt and add into the frosting. Alternatively, you can also use milk or semi-sweet chocolate if you have a strong preference.

Tips for Making the Best Chocolate Raspberry Mousse Cake

• When making the chocolate mousse, chill your mixing bowl and whisk attachment in the freezer. It makes it easier and quicker to whip up the whipped cream for the mousse.
• Ingredients at room temp mix together better! Set out any cold ingredients ahead of time.
• Be sure to properly measure your flour (spoon into the cup measure, then level). Or better yet, use a kitchen scale to measure your dry ingredients.
• Mix the cake batter just until the ingredients are incorporated. This will ensure your cake layers are tender and fluffy.
• Use a scale to weigh your cake pans as you fill them. Make sure each pan has the same amount of batter will make your cake layers bake to the same height and bake more evenly.
• Bang your cake pans on the counter before putting it in the oven. This brings any big air bubbles that are trapped in the batter to the surface.
• Level your room temperature or thawed cake layers with a serrated knife to make them easier to stack.
• Chill your cake layers in the freezer for about 20 minutes before assembling the cake. It makes it so much easier to stack and frost them!

Making this Chocolate Raspberry Mousse Cake in Advance and Storage Tips

• Make your cake layers in advance and freeze them. It breaks the process up and makes it more approachable.
• The chocolate mousse can also be made in advance! Make it up to 2 days in advance and store in the fridge.
• Make your chocolate frosting ahead of time or save any leftover frosting! Store in an airtight container in the fridge for up to a month.
• This frosting can also be stored in the freezer for up to 3 months! Just be sure to give it a good stir once it thaws to make it nice and smooth again.
• This cake can last in the fridge for up to 2 days. I don’t recommend storing it longer than that as the raspberries can start to spoil.

Let Me Know What You Think

If you try this chocolate raspberry mousse cake recipe, I’d love to hear what you think! Please leave a rating below and a comment to let me know your thoughts.

Other Recipes You Might Like: