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I have a serious problem.  I obsess over things.  All it takes is for the small seed of an idea to be planted, and the idea grows at an exponential rate and grabs hold of my brain.  Then, it won’t let go.  It’s this tendency to obsess that will lead me to do things like read a big book or watch an anime series in its entirety in a day or two, or go through dozens of web pages for “research” purposes when there’s a recipe or dish that catches my interest.

This is exactly what happened about a month ago, when a coworker asked me if I could make a cake with Kit Kats (her favorite candy bar).  Well, several hours (okay, maybe DAYS) and hoards of web pages later, my mind was made up.  The seed was officially planted.  Challenge accepted.I used Recipe Girl’s version as my main inspiration.  However, there were some issues that I had with the majority of the recipes that I came across.  First off, there were no actual Kit Kats in any part of the cake.  They were just decoration on the outer edge.  Secondly, most used boxed cake mix and chocolate buttercream or store-bought frosting.  If you’re loading a cake full of candy bars, then any type of buttercream frosting is probably going to be WAY too sweet.  I fixed the first issue by making a chocolate mousse with chopped up Kit Kats folded into it as a filling.  The second issue, I went with my usual chocolate cake recipe, and a bittersweet chocolate ganache glaze.

Wilton makes these nifty pans that are shaped to make fillable cakes.  Your baked cake layers end up with an indentation in the center that you can fill with creams and whatnot.  Use your favorite cake recipe.  I recommend a moist chocolate cake.  If you don’t have a set of fillable pans, you can probably layer it like you would to make the Oreo Cake.

A good chocolate mousse is made up of a chocolate custard and heavy cream whipped to stiff peaks.  You’ll want about a cup of chopped Kit Kat pieces.  Fold your chocolate custard into your whipped cream until no streaks remain.  Set about 1 cup of the mousse aside, then fold in your Kit Kat pieces.  Use it to fill the center of your cake.

I have to apologize for not having photos of the cake layers being filled.  Epic fail on my part.  So, we’ll be skipping straight to our filled cake.

When you have filled and assembled the cake, you’re going to want to set it on a wire rack over a baking sheet.  The parchment paper isn’t necessary, but makes cleanup less of a headache.

Place the assembled cake in the refrigerator, then unwrap your Kit Kats.  Break them apart in pairs.  You can do it in singles, too.  But, pairs will make the process go a lot quicker.  Make your chocolate ganache, then let it cool until it starts to thicken slightly.

Once the cake is sufficiently cool, take it out of the refrigerator and pour the ganache over the cake.  I find it best to start at the center of the cake and work your way out in a circle.  You may need to tilt the cake a few times to get the ganache to cover the sides of the cake.  The good news is that you don’t need full or flawless coverage on the sides.  Let the cake sit for a few minutes for the ganache to start to set (you can put it in the refrigerator to help it along, but make sure you don’t let it get too firm).  Then, start pressing your Kit Kats along the outer edge of the cake.  You can use leftover ganache as “glue” if any of them give you a hard time.  Your Kit Kats may not reach the top of your cake.  That’s fine.  Just take some of that leftover mousse, put it in a piping bag with a fancy tip, and pipe a decorative border around the top.

And, if you’re feeling extra-fancy, you can also decorate the top of the cake.

Once you’ve decorated it as you like, it’s ready to go back in the refrigerator to set.  I recommend making a day ahead, but wait at least 4-hours if you’re not that patient.  You need to allow enough time for the chocolate mousse in the center to set up properly.

As you can see, this cake is a stunner.  My coworker was very pleased.  Plus two points for job security!

There you have it!  It’s a lengthy process, but the end result will look and taste impressive.  Make sure you use the best chocolate that you can afford for your mousse and ganache.  You’ll definitely taste the difference.

Kit Kat Cake

Ingredients

• 1 recipe 2-layer chocolate cake (Recommended: One Bowl Chocolate Cake)
• Approximately 4 cups of chocolate mousse (Recommended: Heavenly Chocolate Mousse)
• Approximately 2 cups of chocolate ganache (Recommended: Chocolate Ganache)
• 10 regular-sized Kit Kat bars, unwrapped and broken into pairs
• 1 cup Kit Kat bites, chopped

Directions

Prepare your cake according to your recipe’s directions.  Allow to cool completely on a wire rack, then remove from pans and refrigerate until ready to use.

Prepare your chocolate mousse according to the recipe directions.  Set about 1 cup of mousse aside, then fold the pieces of chopped Kit Kat bites into the mousse.

Remove the cake layers from the refrigerator, then fill with the mousse mixture and assemble.  Place on a wire rack set over a baking sheet and refrigerate for about 20-30 minutes.

Prepare the chocolate ganache according to recipe directions, and allow to cool slightly.  Remove the assembled cake from the refrigerator and pour the ganache over the cake, tilting the cake as needed to coat the sides.  Let stand until ganache begins to set, then press Kit Kat bars around the outside of the cake, adding ganache to the backs of the candy bars as needed.

Using a piping bag prepared with a star tip, pipe the remaining chocolate mousse along the top border of the cake.  Top with additional swirls of mousse and Kit Kat pieces, if desired.  Refrigerate at least 4 hours before serving.