Easy Chocolate Layer Cake with Chocolate Mousse Filling

Easy Chocolate Layer Cake with Chocolate Mousse Filling

Adapted from The Pioneer Woman

This recipe makes a three-layer cake using three 9″ baking pans.

For the cake:

•  3 C flour
• 3 C sugar
• 1/4 t salt
• 4 heaping T cocoa
• 2 heaping T ultra-dutched cocoa (you can also use all regular cocoa)
• 3 sticks of butter
• 1 1/2 C boiling water
• 3/4 C milk mixed with 3/4 T lemon juice or white vinegar (I use this in lieu of buttermilk so I don’t have to buy a whole quart while only needing 3/4 C)
• 3 eggs
• 1 1/2 t baking soda
• a good shot of vanilla extract

For the mousse:

• 1 pint heavy cream
• 3 oz semi-sweet chocolate or chips
• 2 oz bittersweet chocolate (you can also use all semi-sweet or all bittersweet or even bar milk chocolate like Hershey’s, or a combination of some of the above)
• a dash of vanilla extract

For the frosting:

• 1 3/4 sticks of butter
• 3 heaping T cocoa
• 1 heaping T ultra-dutched cocoa
• 6 T milk
• 1 lb (that’s right – a pound) minus 1/2 C powdered sugar
• a splash of vanilla

Prepare the mousse:

The mousse needs to be chilled for a few hours to overnight, so be sure to make it in advance.

Place the chocolate in a bowl and pour 1/2 C of cream on top. Microwave for one minute, or until the chocolate and cream mixture can be whisked into smooth ganache (alternatively, use a sauce pan set over low heat to this end, but be sure to stir frequently).

Combine the remaining cream and the vanilla and whip until firm peaks form. Pour the ganache over the whipped cream, and continue to whip at low speed until incorporated (be careful to not over-whip, or the mixture will curdle).

Refrigerate for a couple of hours to overnight.

This mousse is wonderful on its own or topped with whipped cream (cause you can never have enough cream), or as a soft filling for a layer cake or roulade (how is my spelling today?).

Prepare the cake:

Preheat the oven to 350 degrees F. Coat three 9″ cake pans with baking spray (I use PAM “Flour” variety).

In a large bowl, mix together flour, sugar, and salt.

In a separate bowl, whisk together milk, vinegar or lemon juice, baking soda, eggs, and vanilla.

Melt the butter in a medium sauce pan and stir in the cocoa. Pour in the boiling water and allow to bubble for a few seconds. Remove from heat and pour the contents of the pot into the dry ingredients. Stir to combine.

Add the wet ingredients to the chocolate-flour mixture and stir until the batter is uniform.

Distribute the batter evenly between the cake pans and bake for 20 minutes.

Allow the layers to cool slightly in the pans on cooling racks before inverting carefully onto the racks. Cool completely before assembling and frosting.

Prepare the frosting:

Melt the butter and add the cocoa. Allow to bubble for a moment.

Off the heat, stir in the powdered sugar, milk, and vanilla. Be sure to stir thoroughly to avoid powdered-sugar lumps in the finished product.

The frosting will be too warm for spreading at this point, so chill it briefly until cool and spreadable.

Assemble the cake:

Note: a cake stand is awfully useful for this, as well as two offset icing spatulas – a large one and a small one. In fact, if you are a beginner, these three tools can make all the difference between feeling like a failure and feeling like a million bucks.

Begin by slicing the mounded tops off the cake layers with a long, sharp serrated knife (I used my 8″ Wusthof bread knife for this purpose). You don’t need to be extremely precise – you just want to make them reasonably flat and even. Do not skip this step.

Dab a bit of the chilled mousse in the center of the cake stand to “glue down” the first layer.

Transfer the first trimmed layer carefully onto the stand, with the flat side facing up (the side that was in the immediate contact with the bottom of the baking pan).

Slide a few strips of waxed paper (like three or four) about one inch in under the cake all the way around. This is done to “line” the stand and catch any stray frosting and filling, assuring that your cake and stand look neat after the cake is fully frosted (we will be removing the waxed paper after the cake is frosted and the frosting has had the chance to firm up and set in the fridge).

Spread half of the mousse on top of the first layer, smoothing it out with a large offset spatula.

Place the second layer on top of the first and spread the rest of the mousse on top of the second layer.

Place the third layer on top of the second and press down gently. Use the small offset spatula to smooth out the mousse oozing from in-between the layers over the sides, thus creating a thin so-called “crumb” coat.

Refrigerate the cake for approximately half an hour, or until the mousse has had the chance to firm up.

Now spread the frosting all over the finished cake and smooth it out in your preferred manner. Don’t worry if it isn’t perfect – people will still be impressed. Especially after they taste it. Seriously, don’t. You don’t owe anything to anybody, at least as far as cake frosting is concerned.

Refrigerate the fully-iced cake to set the frosting, another 30 minutes or so, but be sure to remove the cake from the fridge before the glaze turns hard.

Pull the waxed paper pieces carefully from under the cake.

(I kept my cake on the counter from then on, including for an hour and a half prior to serving.)

Cut into thin wedges and serve.