Jump to Recipe Jump to Video Print Recipe

This Chocolate Hazelnut Layer Cake is made with soft chocolate sponge, creamy mousses, and a crunchy hazelnut layer, all covered in a glossy chocolate glaze, a stunning dessert that’s completely worth the effort.

This post may contain affiliate links, which means I may earn a small commission at no extra cost to you if you make a purchase through one of these links. As an Amazon Associate, I earn from qualifying purchases.

About This Recipe

If you’ve been baking for a while and want to challenge yourself with something a little more advanced, this Chocolate Hazelnut Layer Cake is the perfect next step. It’s inspired by entremet-style cakes, with multiple layers and textures, but simplified so you can make it at home without any special molds or complicated techniques.

This cake is all about contrast. You’ve got soft, airy chocolate sponge soaked in a rich chocolate syrup, a crisp hazelnut praline crunch layer, and two different mousses; one deep and chocolatey, the other nutty and light. Each bite gives you a mix of textures and flavors that just work so well together. And that glossy ganache glaze on top? It ties everything together and gives the cake that elegant, bakery-style finish.

Even though it may look intimidating, it’s actually a really fun weekend baking project. You don’t need any fancy tools, just some patience and a little bit of time. I made mine in a rectangular shape because I love how clean and modern it looks, but you can absolutely make this as a round cake too. If you have a cake ring, it’ll make layering easier, but even without one, you can still build this cake beautifully.

What You Need To Make Chocolate Hazelnut Layer Cake

For the Chocolate Sponge Cake:

Eggs: Room-temperature eggs work best.
Granulated sugar
Milk: I use whole milk, but skimmed milk will also work.
Vegetable oil: Any flavorless oil, like sunflower or canola oil.
Salt
Unsweetened cocoa powder: I recommend using Dutch-processed cocoa powder for a more intense chocolate flavor, but natural cocoa powder will also work.
Cake flour: This gives the sponge cake a fluffy, airy texture, but all-purpose flour will also work if that’s all you have.
Baking powder

For the Hazelnut Praline Crunch:

Hazelnut praline paste: here’s my homemade recipe; one batch will suffice for this recipe. This can be made 3-4 days in advance. Store in an air-tight jar in the refrigerator and bring back to room temperature before using in the recipe.
Dark chocolate: I use Callebaut’s 54% cocoa Belgian chocolate.
Feuilletine: Here’s my homemade feuilletine recipe. One batch will be more than enough for this recipe. This can be made up to a week in advance, stored in an air-tight container at room temperature.
Chopped hazelnuts: This is optional, but it adds more crunchiness to the crunch layer! As well as increasing the hazelnut flavor in the cake.

For the Chocolate Mousse

Dark chocolate
Granulated sugar
Heavy cream: Make sure it’s chilled and has a fat percentage of at least 35% or higher, otherwise it will not whip up.
Egg yolks: Give the mousse a rich texture and flavor.

For the Hazelnut Mousse

Heavy cream: Make sure it’s chilled and has a fat percentage of at least 35% or higher, otherwise it will not whip up.
Hazelnut praline paste: Here’s my homemade hazelnut praline recipe.
Mascarpone: Optional, but stabilizes the mousse.

For the Chocolate Ganache Glaze

Dark chocolate: I use Callebaut’s 54% cocoa Belgian chocolate.
Heavy cream
Unsalted butter

For the Chocolate Simple Syrup (optional)

Water
Granulated sugar
Unsweetened cocoa powder

Pro Tips

Read the recipe fully before starting: There are multiple components, so planning helps a lot.
Work in stages: You can make parts like the praline or sponge ahead of time.
Temperature matters: Make sure mixtures are not too hot or too cold when combining (especially for mousse).
Fold gently: This keeps your mousses light and airy.
Use a piping bag: Makes layering cleaner and easier.
Chill properly: This is key for clean layers and structure.
Don’t rush the glaze: The right temperature gives you that perfect glossy finish.

Storage Instructions

Store the cake in the refrigerator in an airtight container for up to 3–4 days.

For the best texture, let the cake sit at room temperature for about 10–15 minutes before serving so the mousse softens slightly.

This cake can also be frozen (without glaze or with glaze) for up to 1 month, then thawed overnight in the fridge.

FAQs

Is this the same as an entremet cake?

Not exactly, but it’s inspired by one. This is a simpler version with fewer components and no special molds.

Can I make this as a round cake?

Yes! Use a 7–8 inch cake pan and slice into layers.

Do I need a cake ring?

No, but it does make assembly easier and neater.

Can I skip the praline crunch?

You can, but it adds an amazing texture contrast that really elevates the cake.

Why is my mousse not setting properly?

This can happen if the whipped cream was under-whipped or if the mixture was too warm when combined.

This Chocolate Hazelnut Layer Cake is one of those recipes that feels like a true baking project — a little more time, a little more effort, but so incredibly rewarding. The layers, textures, and flavors come together to create something that looks impressive and tastes even better.

If you enjoyed making this, you’ll also love trying my Matilda Chocolate Cake, Chocolate Fudge Snack Cake, Coffee Chocolate Fudge Cake, and Tiramisu Without Mascarpone.

Check out my YouTube Channel for more delicious recipe tutorials! Made one of my recipes? Tag me on Instagram, I would love to see your creations!

Chocolate Hazelnut Layer Cake

Print Recipe Pin Recipe

Prep Time 1 45

Cook Time 25

Chill Time 6 15

Total Time 8 25

Course Dessert

Cuisine French-inspired

Servings 12 servings

Calories 688 kcal

Equipment

Electric stand/mixer
3 Spatulas
9×13-inch rectangle pan
4 Small bowls
2 Medium sized bowls
2 Large bowls
Whisk
2 Small saucepans
2 Piping bags
Pitcher/Jug to pour the flaze over the cake
Pastry brush
Ruler to cut cake layers
Cake board to assemble cake on
Cooling rack and baking sheet lined with parchment paper to glaze the entire cake
2 Large offset spatulas to transport the cake
Kitchen scale and measuring spoons

Ingredients

For the Chocolate Sponge

4 eggs room temperature
140 g granulated sugar
56 g milk room temperature
56 g vegetable oil
1/2 tsp salt
28 g unsweetened cocoa powder
80 g cake flour
1/2 tsp baking powder

For the Hazelnut Praline Crunch Layer

120 g hazelnut praline paste The recipe is available on my site
80 g dark chocolate
65 g feuilletine recipe is available on my site
20 g hazelnuts chopped (optional)

For the Chocolate Mousse

85 g dark chocolate
25 g granulated sugar
30 g heavy cream
50 g egg yolks about 3 egg yolks
210 g heavy cream cold, for whipping

For the Hazelnut Mousse

150 g heavy cream cold
120 g hazelnut praline paste
3 tbsp mascarpone optional

For the Chocolate Ganache Glaze

220 g dark chocolate
250 g heavy cream
1 tbsp unsalted butter

For the Chocolate Simple Syrup

70 g water
70 g granulated sugar
5 g unsweetened cocoa powder

Instructions

Make the Chocolate Sponge Cake

Preheat your oven to 180°C (350°F). Lightly grease only the bottom of a 9×13-inch pan with butter — do not grease the sides. Set aside.
In the bowl of your stand mixer (or lareg bowl if using a hand mixer), add the eggs and granulated sugar. Whisk to combine.
Place the bowl over a pot of hot (not boiling) water and whisk constantly to gently warm the eggs. This helps them whip better. The mixture is ready when it feels warm to the touch (about 42°C).
Immediately beat the mixture on high speed using a whisk attachment until it becomes very light, thick, and fluffy. You’ll know it’s ready when you lift the whisk and the batter falls in ribbons that take a few seconds to disappear.
Reduce the speed to low and beat for another 4–5 minutes until the mixture looks glossy and smooth.
In a small bowl, whisk together the cocoa powder, milk, and vegetable oil until completely smooth and lump-free.
In a separate small bowl, sift together the cake flour and baking powder
Turn off the mixer. Add the dry ingredients to the egg mixture and gently fold using a spatula just until combined. Do not overmix.
Add the cocoa mixture and fold again until fully incorporated, making sure not to deflate the batter.
Pour the batter into the prepared pan and smooth the top.
Bake in the center of the oven for 25 minutes, or until a toothpick inserted into the center comes out clean.
Allow the cake to cool completely in the pan.
Once cooled, remove and cut into 3 equal rectangles (approximately 4×9 inches each).
(Alternatively, bake in a round pan and slice into 3 layers.)

Make the Chocolate Mousse

Melt the chopped dark chocolate in the microwave in 30-second intervals, stirring in between, or use a double boiler. Set aside to cool slightly (it should be warm, not hot).
In a small saucepan, combine the granulated sugar and 30g heavy cream. Whisk and place over medium heat until it just begins to simmer.
In a separate bowl, whisk the egg yolks until smooth.
Slowly pour the hot cream mixture into the egg yolks while whisking continuously (this prevents scrambling).
Pour the mixture back into the saucepan and cook over low heat, whisking constantly, until it slightly thickens and steam begins to rise. This takes about 20–30 seconds. Do not overcook.
Remove from heat and transfer back into the bowl. Beat using a hand mixer or whisk until the mixture becomes pale, thick, and creamy. This is your pâte à bombe.
The pâte à bombe should feel cold or room temp. to touch. Next add the melted chocolate in two batches, folding gently to combine.
In a separate large bowl, whip the cold heavy cream to stiff peaks.
Add the chocolate mixture into the whipped cream in two batches, folding gently until smooth and fully combined.

Make the Hazelnut Mousse

In a large bowl, whip the cold heavy cream to stiff peaks.
In a separate small bowl, mix the hazelnut praline paste and mascarpone until smooth.
Add the praline mixture into the whipped cream and gently fold until fully combined.

Make the Hazelnut Praline Crunch Layer

Melt the chopped dark chocolate in the microwave in 30-second intervals until smooth.
Add the hazelnut praline paste and mix until fully combined.
Add the feuilletine and chopped hazelnuts, and mix until everything is evenly coated.

Make the Chocolate Simple Syrup

In a small saucepan, combine water, sugar, and cocoa powder.
Whisk well and place over medium heat. Bring to a simmer.
Remove from heat and allow to cool completely before using.

Assemble the Cake

Transfer both mousses into piping bags for easier assembly.
Place the first cake layer onto a cake board. Use a pastry brush to soak it evenly with chocolate simple syrup.
Pipe a border of chocolate mousse around the edges of the cake.
Add the hazelnut praline crunch layer inside the border and spread it evenly.
Pipe a thick layer of chocolate mousse over the crunch layer and smooth it out.
Place the second cake layer on top and soak again with syrup.
Pipe a layer of hazelnut mousse and spread evenly.
Add a thin layer of chocolate mousse on top and smooth it out.
Place the final cake layer on top and soak with more syrup.
Use the remaining chocolate mousse to cover the top and sides of the cake, smoothing it out like frosting.
Chill the cake for at least 6 hours, preferably overnight.

Glaze the Cake

In a microwave-safe bowl, combine chopped chocolate, heavy cream, and butter.
Heat in 30–40 second intervals, stirring in between, until fully melted and smooth.
Let the ganache cool to 40–45°C before pouring.
Place the chilled cake on a cooling rack set over a lined tray.
Pour the ganache evenly over the cake, allowing it to drip down the sides.
Use a knife to release any ganache stuck between the cake and rack.
Carefully transfer the cake to a serving plate using offset spatulas.
Chill for 10–15 minutes to set.
Slice and enjoy, you earned this one!