7 Layer Oreo Chocolate Mousse Cake

If you are looking for a dessert to impress, this 7 Layer Oreo Chocolate Mousse Cake is exactly what you are seeking. It tastes as good as it looks!

I had two dessert auctions to bake for this weekend. Watching “Zumbo’s Just Desserts” on Netflix inspired me to go a bit bigger and more grand for the MOPS auction.

For the Young Life auction, I did a tried and true favorite, my Key Lime Pie. This one is is a lot more simple than the 7 Layer Oreo Chocolate Mousse Cake I’m sharing today.

Both desserts flew off the table at auction time.

On another note, if you are making this cake for an Oreo party, you’ll definitely want to check out my Oreo Games.

7 Layer Oreo Chocolate Mousse Cake

Before moving on, I need to give much credit to where credit is due. I was totally inspired by this Tripe Peanut Butter Cake Recipe and Video Tutorial by Ashlee Marie.

She is the genius behind the design, and I’m also major crushing on her website. I want to encourage EVERYONE to head to her site and see if you fall in love with it too.

While this is her design, and I used her video tutorial for structure and decorations, I am offering up a different variation of flavors. I would explore both recipes and decide what fits your needs best.

This recipe will ask you to make cake, mousse, ganache and two types of buttercream.

NOTE: THIS CAKE WILL DO BEST WHEN KEPT IN THE REFRIGERATOR UNTIL SERVED. THREE OF THE INTERIOR LAYERS ARE A CHOCOLATE MOUSSE, WHICH WILL LOSE STABILITY AS IT WARMS.

I MADE THIS CAKE FOR A DESSERT AUCTION. IT HAD TO ARRIVE EARLY AND THEN SAT THROUGH A FEW HOURS AT THE AUCTION. WHEN IT WAS FINALLY TIME FOR THE DESSERT AUCTION, IT WAS LEANING SLIGHTLY.

The Best Oreo Cake Recipe – Ingredients

• 2 2/3 cups water
• 6 eggs
• 2 cup sour cream
• 2 tsp vanilla
• 2 boxes white cake mix
• 2 cup sugar
• 2 cup flour
• 1/4 tsp salt
• Container of Oreos

The Best Oreo Cake Recipe – Directions

• Mix the water, eggs, sour cream, and vanilla with paddle attachment.
• Add the other four ingredients and beat slowly for 30 seconds. Then mix on high for 2 minutes.  
• Pour batter evenly into 8″ cake pans, filling about 2/3 of the way up. I had left over batter each round so made some mini cakes too. You will need a total of 4 – 8″ cakes. Please follow my baking instructions at Cake Making 101 to ensure your cakes don’t stick to the pan.
• Bake for 35-40 minutes or until cakes springs back when pressed in the center. You can also check it with a toothpick.

My white velvet cake recipe is my go to when it comes to baking cakes. Therefore, I simply adapted this recipe by adding Oreos.

Chocolate Mousse – Ingredients

• 2 1/4 teaspoon gelatin powder
• 3 tablespoon water
• 18 ounces semisweet chocolate, coarsely chopped
• 6 tablespoons sugar
• 4 1/2 cups cold heavy cream

Chocolate Mousse – Directions

1. In a small bowl, sprinkle the gelatin evenly over cold water. Let it sit for 5 minutes.
2. Combine chocolate and sugar in a medium bowl, set aside.
3. Bring 1 1/2 cup of the cream to a simmer in a small saucepan over medium-high heat, stirring occasionally to prevent a film from forming on the top
4. Remove cream from heat, and add the softened gelatin. Stir until completely dissolved.
5. Pour the cream over the chocolate and whisk until chocolate is melted and the mixture is smooth. If chocolate doesn’t melt and smooth completely, place your glass bowl over a pot with a few inches of bowling water (created a double boiler), and whisk until smooth.
6. Cool to room temperature, stirring occasionally. The mixture will thicken slightly.
7. Using an electric mixer or stand mixer fitted with the whisk attachment, whisk the remaining 3 cup cream at medium speed until mixture thickens, about 30 seconds. Increase the speed to high and whip until soft peaks form.
8. Use a hand whisk to mix in 1/3 of the whipped cream into the chocolate mixture.
9. Next, use a rubber spatula to fold the remaining whipped cream into the chocolate mixture until completely incorporated.

The Best Buttercream Frosting Recipe – Ingredients

• 1 cup butter flavored shortening (room temperature)
• 1 cup unsalted butter (room temperature)
• 2 lbs powdered sugar, or about 8 cups (sifted for best results)
• 1/2 teaspoon salt
• 2 teaspoons vanilla extract
• 4-6 oz heavy whipping cream

The Best Buttercream Frosting Recipe – Directions

1. In a mixing bowl, cream shortening  and butter until fluffy.
2. Add sugar, one cup at a time, mixing a bit between each addition. When adding sugar, you will want to start the mixer slowly so it doesn’t explode everywhere. Continue creaming until well blended.
3. Add salt, vanilla, and 6 ounces whipping cream. Blend on low speed until moistened.
4. Finally, beat at high speed until frosting is fluffy, 1-2 minutes.

The Best Chocolate Buttercream Frosting Recipe – Ingredients

• 1/2 cup butter flavored shortening (room temperature)
• 1/2 cup unsalted butter (room temperature)
• 1 lbs powdered sugar, or about 4 cups (sifted for best results)
• 1/2 cup unsweetened cocoa, sifted
• 1/4 teaspoon salt
• 1 teaspoons vanilla extract
• 3-4 oz heavy whipping cream

The Best Chocolate Buttercream Frosting Recipe – DIRECTIONS

1. In a mixing bowl, cream shortening  and butter until fluffy.
2. Add sifted cocoa powder and mix until fully combined.
3. Add sugar, one cup at a time, mixing a bit between each addition. When adding sugar, you will want to start the mixer slowly so it doesn’t explode everywhere. Continue creaming until well blended.
4. Add salt, vanilla, and 3-4 ounces whipping cream. Blend on low speed until moistened. Beat at high speed until frosting is fluffy, 1-2 minutes.

Chocolate Ganache Recipe

I used Ashlee Marie’s Chocolate Ganache Recipe. Here’s the deal though: Mine did not drip as gorgeous as hers did. It wasn’t as smooth and perfect either.

The problem is, I didn’t follow her recipe to the letter. I did use a higher end chocolate chip, but she says “Don’t use chocolate chips!” I disobeyed, and I didn’t get the results.

Lesson learned: Just follow the recipe!

Other ganaches I have made call for butter, so maybe that is something you could explore.

Cookies and Candies Used to Decorate the 7 Layer Oreo Chocolate Mousse Cake

• Oreo Cookies
• Oreo Cookie Minis
• York Patties
• Mini York Patties
• Lindt Dark Chocolate Truffles
• Oreo Cookie Chocolate Bars, Cut into Varying sizes
• Mini Kit Kats
• Rolos
• Junior Mints

How to Assemble a 7 Layer Oreo Chocolate Mousse Cake

Time for construction!

Please, please, please visit the video tutorial Ashlee Marie put together. It will make everything so clear!

Also, I provide a visual tutorial after all of these words.

Here’s the quick low down:

• Prepare the cakes and cool completely before assembling. The recipe provided makes 4 – 8″ cakes with some batter left over. Please read my Cake Making 101 post for all of my baking tips, including the best way to get cakes to not stick to the pan. I had to make the recipe in two batches since I only had 2 – 8″ cake pans.
• Using a leveling tool, cut each cake to a 1″ size.
• Make the chocolate mousse. The recipe provided makes enough for 3 layers. When stacking the cake, you will want to divide the mousse into 3 parts evenly. A kitchen scale is the tool you will need to make this happen. Each layer should measure an inch. You may have some leftover mousse, which makes a tasty treat.
• When it is time to layer your cake, you will need 4″ acetate cake collars.
• Take your bottom layer of cake and place it on an 8″ cardboard cake board.
• Wrap this bottom layer in the acetate cake collar, taping the end in place.
• Next, add an even, 1″ layer of mousse, spreading flat.
• Continue stacking cake and mousse. After the first three layers, you will need to tape another acetate cake collar to accommodate the 7 layer Oreo chocolate mousse cake. I had my cake stacked on top of a revolving cake stand to make decorating easier.
• Once assembled, place in the refrigerator to set for at least 3 hours. Make sure to cover the top with plastic so the cake does not dry out.
• After it is set, peel away the acetate edges.
• Time to make your buttercream frosting recipe.
• Using the plain buttercream, do a crumb coat layer following my instructions in the link.
• Set in the refrigerator.
• While buttercream is setting, make your chocolate buttercream recipe.
• Put both the chocolate buttercream and the remaining plain buttercream in two separate piping bags affixed with a large round piping tip.
• My cake was seven inches high. I therefore piped 7 different layers of frosting. Each buttercream frosting layer was 1 inch tall and alternated from the white to the chocolate frosting. I started with the white on the bottom because the bottom tier was the cake, and I wanted the exterior layers to match the interior layers.
• Once piped, use a tall 10″ cake scraper (i.e. dough cutter) to even out the sides. Please watch the video tutorial linked to above to see how it works. You want to apply even pressure as you scrape away a small amount of frosting on the edges to provide a smooth, striped look. I used paper towels to wipe away the frosting on my cake scraper as I continued around the edge.
• Frost the top with your plain buttercream and smooth.
• You should now have a 7-inch tall, striped cake. Phew. Almost there.
• Next, make the ganache.
• Apply the ganache in drips to the edge of the cake and then smooth the ganache over the top. Again, Ashlee Marie’s video tutorial will help. Her ganache turned out so much more attractive than mine.
• Time to decorate with the goodies.
• I took all the candies and cookies above and layered them, swooping down one side of the cake.

How to Assemble a 7 Layer Oreo Chocolate Mousse Cake – Picture Tutorial

The Best Oreo Cake Recipe

This is a delicious Oreo Cake Recipe, which is used for my 7 Layer Oreo Chocolate Mousse Cake

5 from 1 vote

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Prep Time 10 minutes mins

Cook Time 40 minutes mins

Cooling Time 30 minutes mins

Total Time 50 minutes mins

Course Dessert

Cuisine Baking

Ingredients

  

THE BEST OREO CAKE RECIPE – INGREDIENTS

• 2 2/3 cups water
• 6 eggs
• 2 cup sour cream
• 2 tsp vanilla
• 2 boxes white cake mix
• 2 cup sugar
• 2 cup flour
• 1/4 tsp salt
• Container of Oreos

Instructions

 

THE BEST OREO CAKE RECIPE – DIRECTIONS

• Mix the water, eggs, sour cream, and vanilla with paddle attachment.
• Add the other four ingredients and beat slowly for 30 seconds. Then mix on high for 2 minutes.
• Pour batter evenly into 8″ cake pans, filling about 2/3 of the way up. I had left over batter each round so made some mini cakes too. You will need a total of 4 – 8″ cakes. Please follow my baking instructions at Cake Making 101 to ensure your cakes don’t stick to the pan.
• Bake for 35-40 minutes or until cakes springs back when pressed in the center. You can also check it with a toothpick.

Keyword cake

Chocolate Mousse Recipe

This is the chocolate mousse recipe that works as some of the layers for my 7 layer Oreo Chocolate Mousse Cake.

5 from 1 vote

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Course Dessert

Cuisine Baking

Ingredients

  

CHOCOLATE MOUSSE – INGREDIENTS

• 2 1/4 teaspoon gelatin powder
• 3 tablespoon water
• 18 ounces semisweet chocolate coarsely chopped
• 6 tablespoons sugar
• 4 1/2 cups cold heavy cream

Instructions

 

CHOCOLATE MOUSSE – DIRECTIONS

• In a small bowl, sprinkle the gelatin evenly over cold water. Let it sit for 5 minutes.
• Combine chocolate and sugar in a medium bowl, set aside.
• Bring 1 1/2 cup of the cream to a simmer in a small saucepan over medium-high heat, stirring occasionally to prevent a film from forming on the top
• Remove cream from heat, and add the softened gelatin. Stir until completely dissolved.
• Pour the cream over the chocolate and whisk until chocolate is melted and the mixture is smooth. If chocolate doesn’t melt and smooth completely, place your glass bowl over a pot with a few inches of bowling water (created a double boiler), and whisk until smooth.
• Cool to room temperature, stirring occasionally. The mixture will thicken slightly.
• Using an electric mixer or stand mixer fitted with the whisk attachment, whisk the remaining 3 cup cream at medium speed until mixture thickens, about 30 seconds. Increase the speed to high and whip until soft peaks form.
• Use a hand whisk to mix in 1/3 of the whipped cream into the chocolate mixture.
• Next, use a rubber spatula to fold the remaining whipped cream into the chocolate mixture until completely incorporated.

The Best Buttercream Recipe

This is my go-to buttercream recipe that I also use for this 7 Layer Oreo Chocolate Mouse Cake

5 from 1 vote

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Prep Time 10 minutes mins

Course Dessert

Cuisine Baking

Ingredients

  

THE BEST BUTTERCREAM FROSTING RECIPE – INGREDIENTS

• 1 cup butter flavored shortening room temperature
• 1 cup unsalted butter room temperature
• 2 lbs powdered sugar or about 8 cups (sifted for best results)
• 1/2 teaspoon salt
• 2 teaspoons vanilla extract
• 4-6 oz heavy whipping cream

Instructions

 

THE BEST BUTTERCREAM FROSTING RECIPE – DIRECTIONS

• In a mixing bowl, cream shortening and butter until fluffy.
• Add sugar, one cup at a time, mixing a bit between each addition. When adding sugar, you will want to start the mixer slowly so it doesn’t explode everywhere. Continue creaming until well blended.
• Add salt, vanilla, and 6 ounces whipping cream. Blend on low speed until moistened.
• Finally, beat at high speed until frosting is fluffy, 1-2 minutes.

Keyword buttercream, frosting

The Best Chocolate Buttercream Recipe

This is the best chocolate buttercream recipe, and it is part of the outer layer of my 7 Layer Oreo Chocolate Mousse Cake. 

5 from 1 vote

Print Recipe Pin Recipe Rate this Recipe

Prep Time 10 minutes mins

Course Dessert

Cuisine Baking

Ingredients

  

THE BEST CHOCOLATE BUTTERCREAM FROSTING RECIPE – INGREDIENTS

• 1/2 cup butter flavored shortening room temperature
• 1/2 cup unsalted butter room temperature
• 1 lbs powdered sugar or about 8 cups (sifted for best results)
• 1/2 cup unsweetened cocoa sifted
• 1/4 teaspoon salt
• 1 teaspoons vanilla extract
• 3-4 oz heavy whipping cream

Instructions

 

THE BEST CHOCOLATE BUTTERCREAM FROSTING RECIPE – DIRECTIONS

• In a mixing bowl, cream shortening and butter until fluffy.
• Add sifted cocoa powder and mix until fully combined.
• Add sugar, one cup at a time, mixing a bit between each addition. When adding sugar, you will want to start the mixer slowly so it doesn’t explode everywhere. Continue creaming until well blended.
• Add salt, vanilla, and 3-4 ounces whipping cream. Blend on low speed until moistened. Beat at high speed until frosting is fluffy, 1-2 minutes.

Keyword chocolate, chocolate buttercream, chocolate frosting

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