Oreos and Chocolate Mousse Layered Cake

No wonder I’m growing… horizontally – I have been eating way too many cakes lately *cries* (check out the culprits: this, this and this)

But well, the idea of having a chocolate mousse and Oreo filling cake is too good to pass.

The chocolate genoise is simply delicious – it’s very light, airy and porous. It absorbs syrup readily so it can soak up lots of delicious flavours (imagine brushing it with a rum-flavoured syrup!) Using a genoise as a cake base helps to lighten the overall flavours – I can finish one thick slice by myself without feeling that it’s too rich.

The only problem is that I can’t slice a cake… for nuts! Well, my skill has definitely improved from the past but there’s no consistency – most of the times I still end up with cake slices of varying heights. I really need to practice more often…

The chocolate mousse portion can’t be any simpler – it’s made with just chocolate and whipping cream. I used Varlhona dark chocolate, which gives a very deep and rich chocolate flavour – absolute YUMS.

I had some leftover Oreo cream cheese frosting from a previous recipe – because it’s not enough to frost the whole cake, I decided to use it as a filling. I originally wanted to mix some huge chunks of Oreos into the filling but in the end was too lazy to do so… so plain it is!

As for the frosting, I tried out a new recipe that requires cooking flour and milk into a paste and adding it into a creamed butter and sugar mixture. I like the recipe because the frosting is very steady – what I mean is that even though the temperature was pretty warm in the kitchen that day, the frosting did not melt or ooze or anything. Of course it’s still better chilled, but it doesn’t soften as fast as a cream cheese frosting and it pipes really well. As for taste-wise, it’s milky and creamy – not my favourite but I’m hoping to make a chocolate version of this soon.

Overall, it’s a light, moist, soft and delicious cake. Even my mom who’s not fond of cream cakes finds this delicious! I am 200% certain that this cake will definitely be a crowd-pleaser – who doesn’t love chocolate, Oreos and cake altogether? 😉

I’ve not taken photos of how to make the individual components (except for the genoise in my previous post), but I’ve taken photos of the assembly. It would definitely be easier if you have a lazy susan / cake decorating turn table as it makes the decorating much easier.

Start off with a layer of chocolate genoise.

I don’t have a cake board that is 7×3.5-inch, so I made my own by cutting a piece of cardboard and then wrapping it with two layers of aluminum foil – an instant cake board done!

Brush with a layer of syrup.

There’s no need to drench the cake in syrup, just a thin layer will do. The syrup will help to prevent the cake from drying out too fast when stored in the refrigerator. It can also help to boost a bit of flavours if you flavoured your syrup with alcohol 😉

Spread a layer of chocolate mousse.

I’m using the most simple recipe for the chocolate mousse – just Varlhona dark chocolate and whipping cream. It’s so easy and it’s so delicious!

Brush both sides of the second layer with syrup.

Top it with some delicious Oreo filling.

This is my leftover Oreo cream cheese filling from this recipe. So, so, so delicious!

Up goes the third layer.

And smooth it with the remaining mousse.

The last layer goes up.

Cover the sides and top with a buttercream frosting, then decorate it!

You can do a crumb coat and refrigerate the cake first before applying a proper layer of frosting – it will prevent the cake crumbs from getting into the frosting – that is if you want to decorate the cake plain with the frosting.

I wanted to coat mine all over with Oreos crumbs, so I just slapped the frosting on and press the Oreo crumbs all over.

Something like this!

Bake one today!

I’m submitting this to Aspiring Bakers #18: Layers of Love (April 2012) hosted by Sam of Sweet Samsations!

This recipe consists of four components:

1. Chocolate Genoise;
2. Chocolate Mousse;
3. Frosting / Filling; and
4. Simple Sugar Syrup

It’s much, much easier and less complicated to bake and assemble this cake (when compared to this crazy one).

Relax Plan:
Day 1: Make the sugar syrup and keep it refrigerated.
Day 2: Bake the chocolate genoise and store in the refrigerator.
Day 3: Make the mousse and frosting. Assemble the cake and keep it refrigerated. Serve.

Busy Plan:
Day 1: Make the sugar syrup and chocolate genoise. Keep them in the refrigerator.
Day 2: Make the mousse and frosting. Assemble the cake and keep it refrigerated. Serve.

Crazy Plan:
Day 1: Make the sugar syrup, bake the chocolate genoise and make the mousse and frosting. Assemble the cake after the genoise has cooled completely and keep it refrigerated. Serve.

My plan was a busy one and it’s very manageable. One thing to note is that I already had some leftover cream cheese frosting (which is used in the filling) so I made the frosting using lesser amounts than stated in the recipe below. I have provided recipes to both types of buttercream – a cream cheese and a plain version, choose whichever you like! The measurements are not exact (just an estimation of how much you’ll need to fill, frost a thin layer and to pipe the rosettes on top). You may end up with extra filling / frosting – depending on how much you use to frost.

If you don’t want to use Oreo crumbs to coat all around, remember to make double the amount of frosting so that you have enough to frost it completely (mine was a thin layer – just enough so that the Oreo crumbs can adhere onto the cake).

Print Recipe Pin Recipe

Oreos and Chocolate Mousse Layered Cake

Makes a 7 x 3.5 cake, 4-inch tall

By Jasline N.

0.511.523

INGREDIENTS

 

Simple Sugar Syrup

• ▢ 1/3 cup sugar
• ▢ 1/3 cup water
  
  

Chocolate Genoise (step-by-step photos here)

• ▢ 45 grams 1/3 cup + 1 tablespoon plain flour
• ▢ 35 grams 1/3 cup + 1 tablespoon good-quality cocoa powder
• ▢ 4 eggs, cold or at room temperature
• ▢ 100 grams 1/2 cup caster/granulated sugar
• ▢ 45 grams 3 tablespoons hot, melted butter
  
  

Easy Chocolate Mousse

• ▢ 55 grams 2 oz good quality semi-sweet chocolate, chopped
• ▢ 65 ml 1/4 cup whipping cream
  
  

Buttercream #1: Cream Cheese Buttercream

• ▢ 100 grams about 1/2 cup room temperature cream cheese
• ▢ 100 grams about 1/2 cup room temperature unsalted butter
• ▢ 200 – 250 grams, 1 1/2 cups to 2 cups icing sugar, sifted
• ▢ 1/2 teaspoon vanilla extract
• ▢ 3 Oreos, cream removed and crushed to smithereens (and an additional 3-5 pieces roughly crushed for texture if desired)
  
  

Buttercream #2: Tasty Kitchen's Best Frosting

• ▢ 155 ml 2/3 cup milk
• ▢ 3 tablespoons plain flour
• ▢ 150 grams 2/3 cup unsalted butter, at room temperature
• ▢ 150 grams 2/3 cup caster sugar
• ▢ 1/2 teaspoon vanilla extract
• ▢ 3 Oreos, cream removed and crushed crushed to smithereens (and an additional 3-5 pieces roughly crushed for texture if desired)
  
  

Assembly

• ▢ 1 Chocolate Genoise
• ▢ 1 Simple Sugar Syrup
• ▢ 1 Cream Cheese Buttercream or Tasty Kitchen's Best Frosting
• ▢ 10 Oreos, cream removed and crushed (you can leave some big chunks for texture)

INSTRUCTIONS

Simple Sugar Syrup

• Place the sugar and water in a small pot. Bring the mixture to a boil, swirling the pot to dissolve the sugar crystals. Boil for 2 – 3 minutes on high heat then remove the pot from heat. Let cool to room temperature before using.

Chocolate Genoise

• Preheat the oven to 170 degrees Celsius. Grease a 7-inch baking tin and line the bottom with parchment paper. Set aside.
• Sift the flour and cocoa powder together thrice. Set aside.
• Place the eggs in a medium pot or a large metal mixing bowl. Add in the sugar and whisk immediately until combined. You must whisk the sugar immediately into the eggs otherwise lumps will form and it will be very hard to get rid of them later on.
• Hold the pot / mixing bowl over medium-low heat and whisk the egg-sugar mixture constantly, to bring up the temperature until its like baby's milk - warm but not hot. The mixture would be foamy. You can set it directly over the heat, just make sure that you remove it from time to time so you don't end up with cooked eggs.
• Transfer the mixture in the pot into a mixing bowl and whisk it with a hand-held electric mixer on high speed until the bubbles start to disappear. The mixture will triple in volume. Turn the mixer down to low and whisk it for at least 1 minute, to stabilize the air bubbles in the cake batter. The cake batter will leave a trail when you lift up the beaters and will sink and merge back slowly into the batter.
• Sift in half of the flour mixture and gently fold it in until almost all are combined. Sift in the remaining half of the flour mixture and fold until no flour pockets are visible. Do not over-mix.
• Add one-third of the cake batter into the hot, melted butter. Use a smaller spatula and fold the butter into the cake batter thoroughly. Pour the butter-mixed batter back into the rest of the cake batter and fold in gently.
• Transfer the cake batter into the baking tin. Tilt the tin so the batter spreads out evenly and drop it several times on the counter top to burst the uneven air bubbles.
• Bake in the middle rack for 15 to 20 minutes until the cake springs back when touched gently and a skewer inserted into the centre of the cake comes out clean.
• Make ahead:Make the cake one day ahead and store in an air-tight container in a cool place or in the refrigerator.

Easy Chocolate Mousse

• Melt the chocolate and let it cool to lukewarm. Whip the cream to soft peaks formed and fold in the melted chocolate.
• Refrigerate the mousse for 10 to 15 minutes until it has thickened but still soft enough to be spread on the cake. If it has hardened, leave it out at room temperature to soften before spreading it on the cake.

Buttercream #1: Cream Cheese Buttercream

• Using an electric mixer or food processor, beat the cream cheese, unsalted butter and icing sugar together until light and fluffy. Beat in the vanilla extract.
• Remove a quarter of the buttercream and mix into the crushed Oreos. This would be your filling for the cake later on.
• Remove half of the remaining buttercream and transfer it to a piping bag fitted with a star tip to pipe rosettes later on.
• The rest of the buttercream would be used to frost the cake.

Buttercream #2: Tasty Kitchen's Best Frosting

• Pour the milk into a small pot. Whisk in the flour with a wire whisk. Heat the mixture over medium-low heat and whisk constantly, until the mixture has thickened and has the consistency of a brownie mix (it should be very thick, like glue). Remove from heat and let it cool to room temperature completely.
• In a clean mixing bowl, use an electric mixer and whip the softened butter and the sugar until the sugar has been fully incorporated (no graininess remains). Beat in the vanilla extract.
• Scrape the cooled milk-flour mixture into the butter-sugar mixture and whip with the electric mixer until they have all combined together and resembles whipped cream.
• Remove a quarter of the buttercream and mix it with the crushed Oreos. This would be your filling for the cake later on.
• Remove half of the remaining buttercream and transfer it to a piping bag fitted with a star tip to pipe rosettes later on.
• The rest of the buttercream would be used to frost the cake.

Assembly

• Slice the genoise half vertically to get 2 7x3.5-inch rectangles. Slice each half horizontally to get 4 slices of genoise 7x3.5-inch each.
• Place one layer of the genoise on a cake board. Brush with a layer of syrup - don't soak the cake!
• Spread half of the chocolate mousse on top of the cake later, leaving a 1/4-inch border all around.
• Brush the second layer of genoise with syrup on both sides then place it on top of the mousse.
• Spread the Oreos-mixed filling onto the genoise, leaving a 1/4-inch border all around.
• Brush the third layer of genoise both sides with syrup and place it on top of the Oreos filling.
• Spread or pipe the remaining chocolate mousse on the genoise. Brush the last layer of genoise both sides with syrup and place it on top.
• Spread a layer of frosting on the sides of the cake and a thinner layer of frosting on top.
• Hold the cake (with the cake board) in your hand, press the crushed Oreos all over the sides of the cake. If desired, press some of the crushed Oreos on the top of the cake to create a border.
• Pipe rosettes on top of the cake as close to each other as possible and refrigerate till ready to serve.

NOTES

- Cake adapted from recipe Chocolate Raspberry Ruffle Cake by Julia Child: Lessons with Master Chefs
- Frosting adapted from Tasty Kitchen's Best Frosting I've Ever Had

Tried this recipe?Mention @foodiebaker or tag #foodiebaker!

Super Naggy – Mousse:

• How to melt chocolate
  • Get a pot that will allow the large heatproof bowl to sit snugly on it without the bottom of the bowl touch the bottom of the pot. Pour water in the pot until the height of the water comes up to 1 inch. Bring the water to a boil and turn the heat down to the lowest setting.
  • Chop the chocolate to small even-sized pieces and place it in the heatproof bowl. Place the bowl over the pot, making sure that the bowl is not touching the surface of the water at all (preferably at least 1 inch away). Stir the chocolate occasionally with a spatula until all the chocolate has melted and the mixture is smooth.
  • Alternatively, melt the chocolate in a microwave: turn the microwave settings to medium-high. Place the finely chopped chocolate in the heatproof bowl and microwave for 20 seconds. Take it out, give it a stir then microwave it for another 15 to 20 seconds. Repeat until all the chocolate has melted. Don’t microwave it for too long at one go – chocolate burns easily and burnt chocolate is simply gross!
• Substitute the semi-sweet chocolate with dark chocolate or use a mixture of semi-sweet and dark. I used Varlhona dark chocolate this time round.
• Make the mousse the day you want to use it.

Super Naggy – Cream Cheese Buttercream:

• Crushing the Oreos: If you don’t have a food processor like me, simply place the Oreos in a large ziploc bag. Use a rolling pin or a bottle, roll the biscuits until they are all crushed to desired size. You can also whack with the rolling pin but don’t whack it too hard as the ziploc bag may tear.
• This buttercream becomes soft faster at room temperature as compared to Buttercream #2, so do store the cake in the refrigerator and bring it out only 15 minutes before serving them.
• Make the buttercream the day you want to assemble the cake.

Super Naggy; – Tasty Kitchen’s Best Frosting:

• I ran out of flour, so I actually used 2 tablespoons corn starch – works well too!
• If you’re in a rush, place the heated pot of milk-flour mixture into a bowl of ice water. It will help to bring down the temperature of the mixture faster.
• I like to process the caster sugar in a food processor until it’s of a very fine powder before mixing it in – incorporates into the butter much faster in my opinion.
• Make the buttercream the day you want to assemble the cake.

Super Naggy – Assembly:

• To spread the filling evenly on the cake, I find it best to scoop the filling onto the middle of the cake and slowly spread it out. Another method that I like is to place the filling in a piping bag and pipe it – this ensures an even amount of filling being applied (but there would be more to wash up later on).
• Hold the genoise in one hand. Brush it with a layer of syrup and place the syrup side down onto the filling then brush the top with the syrup.
• You don’t have to put a very thick layer of frosting if you’re going to coat it with Oreo crumbs. If you don’t wan’t to coat it with Oreo crumbs, do remember to make double the amount of frosting so you have enough to go around. If you are not coating it with Oreo crumbs, it’d be best to do a crumb coating first so that the cake crumbs don’t get all over the frosting.
• The Oreo crumbs become soft if you store it too long in the fridge, so if you want crunchy Oreos, do coat the cake with Oreos just before serving (crunchy or not, I like them all the same!)