Triple Chocolate Mousse Cake Recipe

This recipe makes enough mousse for about eight 2″-diameter cakes, give or take, depending on the size of your molds. Make sure you have enough freezer space available to accommodate a sheet pan with ring molds.

The whole recipe must be made at least 6 hours before you plan to serve because the mousse needs a chance to set up, but if you like, you can make each step of this recipe on different days to break up the labor, and just keep it in the freezer until serving day.

There will be plenty of cake and chocolate sauce left, which can both be wrapped well and frozen, or enjoyed as a cake sundae by cutting the cake into squares, topping with a scoop of ice cream, and drizzling with chocolate sauce.

Ingredients

For the chocolate cake layer:
1 stick (112 g) unsalted butter
1 1/3 cups (257 g) sugar 
1/2 cup + 2 tablespoons (56 g) cocoa powder
2 large eggs
2 oz (56 g) dark chocolate, melted
1 3/4 cups (210 g) all-purpose flour
1 teaspoon (4 g) baking powder
3/4 teaspoon (3 g) baking soda
1/4 teaspoon (1 g) salt
1/2 cup (118 ml) water
1/2 cup (118 ml) milk

For the dark chocolate mousse:
1 teaspoon (3 grams) powdered gelatin 
2 tablespoons water
1/2 cup (105 g) whole milk
6 oz (175 g) good quality dark chocolate (or use milk chocolate if you prefer), finely chopped
1 1/4 cup (280 g) heavy cream

For the white chocolate mousse:
1/2 cup (105 g) whole milk
6 oz (175 g) good quality white chocolate
1 teaspoon (3 grams) powdered gelatin 
2 tablespoons water
3/4 cup (180 g) heavy cream

For the chocolate glaze and sauce:
4 oz (112g) dark chocolate, finely chopped
1/2 cup (80g) heavy cream 
3 tablespoons light corn syrup
1 tablespoon vegetable oil
1/2 teaspoon vanilla extract

For the chocolate crunch:
1 cup Rice Crispies cereal, or similar rice cereal
2 oz (56 g) dark chocolate

Instructions

Make the chocolate cake layer:

1. All cold ingredients should be at room temperature for better incorporation. Preheat oven to 325 degrees F.
2. Melt the chocolate. I like to chop it up fine, and melt it in the microwave in 30-second intervals. Chocolate burns easily, so stir between every zap. Mine took about 60-90 seconds to melt. Keep it to the side for the moment.
3. Using a tabletop or handheld electric mixer, beat the butter, sugar, and cocoa powder together on medium high speed until smooth, creamy and fluffy, about 3 minutes.
4. Add the eggs, one at a time, until each one disappears into the mix. Be sure to scrape down the sides and bottom of the bowl. The dry, gritty stuff wants to collect at the bottom. Don’t let it win.
5. Pour in the melted chocolate. Hopefully, by now your chocolate came down in temperature a little. It should feel like a warm bath. If it’s too hot, it might melt the butter, and that’s no good. If it’s too cold, it might re-solidify into little bits when it hits the cold bowl. So, warm. We want it warm.
6. In a medium bowl, stir together the dry ingredients, which include flour, baking powder, baking soda and salt. Stir ‘em up good.
7. Combine the milk and the water in a microwave-safe cup and microwave them until hot, about 45 seconds. Like a “too hot” bath.
8. Drop the dry ingredients into the mixing bowl and mix on low speed until MOSTLY combined, and then, with the machine still running, pour in the hot water/milk mixture. Be sure to scrape the bottom of the bowl again. The dry ingredients tend to hide there.
9. Pour the batter into a 18″ x 13″ sheet pan that’s been first sprayed with nonstick cooking spray and lined with parchment. (You can use any sized sheet pan with high sides — just pour in enough batter to come about halfway up the sides. If you have leftover batter, you can pour it into greased muffin tins, and bake mini cakes as well.) Spread it out evenly.
10. Bake in your preheated oven for about 18 minutes. Even though I specify a time amount, everyone’s ovens have a personality of their own, so it’s better to just pay attention to what the cake looks like. It shouldn’t look wet on top and will spring back when lightly pressed with your fingertips. Let it cool to room temperature. (Cake layer can be made a day ahead, if you’d like to break up the labor of this recipe. Wrap the whole thing, sheet pan and all, with plastic very well, and refrigerate.)
11. Cut a cake circle with each ring mold, regardless of which size you’ve decided to use. Place the molds on a parchment-lined sheet pan, one that will fit in your freezer.

Make some dark chocolate mousse:

1. Make sure your dark chocolate is finely chopped and waiting in a large bowl. Resist the urge to eat the shards.
2. First we’ll rehydrate the gelatin (otherwise known as “bloom” the gelatin.) Sprinkle it evenly over a small bowl with the water. In 5 minutes, it’ll have slurped up the liquid and will look, well, gelatinous.
3. Next heat up the milk to a simmer in a small sauce pan. Stay close so it doesn’t boil all over.
4. Turn OFF the heat (This is important. When subjected to high heat, gelatin deteriorates and turns grainy) and then scrape the gelatin blob into the hot milk. Swirl the pan around until it’s completely dissolved. It’ll look like there’s nothing more than milk.
5. Pour this milk/gelatin concoction over the finely chopped chocolate and let it rest for 2 minutes. The heat from the milk will melt down the chocolate. Whisk it up into a smooth pool of goodness. Set it aside and let it cool to lukewarm. Don’t let it reach room temperature or the gelatin may start to set up.
6. Now, with a clean whisk, whip the cream to soft peaks. This texture is easiest to fold into the chocolate.
7. Scoop about a third of the whipped cream into the chocolate and fold in. Since the chocolate is kind of dense and heavy, this will help lighten it up. When we fold in the rest of the cream, it won’t deflate as much. Scrape the sides and bottom of the bowl as you work, gently turning the mix in on itself. Then add the rest of the whipped cream, and gently fold that in.
8. Pour the mousse into the waiting molds, filling them about halfway, without dripping on the insides of the molds. Otherwise when you’re ready to unmold the finished dessert, the sides will look messy. Put the whole tray in the freezer while you make the white chocolate mousse.

Make the white chocolate mousse:

1. The ingredients and method are pretty much the same as the dark chocolate mousse, except there’s less cream to whip.
2. Make sure your white chocolate is finely chopped and waiting in a large bowl.
3. First we’ll rehydrate the gelatin. Sprinkle it evenly over a small bowl with the water. In 5 minutes, it’ll have slurped up the liquid and will look, well, gelatinous.
4. Next heat up the milk to a simmer in a small sauce pan. Stay close so it doesn’t boil all over.
5. Turn OFF the heat (This is important. When subjected to high heat, gelatin deteriorates and turns grainy) and then scrape the gelatin blob into the hot milk. Swirl the pan around until it’s completely dissolved. It’ll look like there’s nothing more than milk.
6. Pour this milk/gelatin concoction over the finely chopped chocolate and let it rest for 2 minutes. The heat from the milk will melt down the chocolate. Whisk it up into a smooth pool of goodness. Set it aside and let it cool to lukewarm. Don’t let it reach room temperature or the gelatin may start to set up.
7. Now, with a clean whisk, whip the cream to soft peaks. This texture is easiest to fold into the chocolate.
8. Scoop about a third of the whipped cream into the chocolate and fold in. Since the chocolate is kind of dense and heavy, this will help lighten it up. When we fold in the rest of the cream, it won’t deflate as much. Scrape the sides and bottom of the bowl as you work, gently turning the mix in on itself. Then add the rest of the whipped cream, and gently fold that in.
9. It gets poured into the molds, most of the way up. Leave some space on top, about 1/8″ – 1/4″ for the chocolate glaze. Pop the tray back into the freezer while you make the glaze and garnish.

Make the garnish:

1. All we need are chopped chocolate and crunchy rice cereal
2. Melt the chocolate in a medium sized bowl by nuking it in a microwave. Start with 30 seconds, stir, then continue with 20 second intervals until it’s completely melted. Chocolate can scorch easily, so it’s best to do the melting in short spurts.
3. Throw in the cereal, and work it around the bowl until it’s completely coated. There’s something very satisfying about doing this. If some of this mix makes it into your gullet, I’ll look the other way.
4. Spread it all out on a parchment-lined sheet pan, keeping it in little flat clusters. This way, the cereal bits touch each other, and can dry in chunks. Pop it in the fridge to set up. (This keeps in the fridge for weeks. Once the chocolate sets up, you can break this up and keep the pieces in a small plastic container.)

Whew! Almost done. Let’s knock out the chocolate sauce/glaze:

1. Pour the heavy cream, corn syrup and oil into a microwave-proof cup and nuke until almost boiling (you might be able to see it gurgling in the cup), about 45 seconds. It will look curdled but pay it no mind. Stir it up to blend.
2. Pour over the chocolate and allow to sit for a minute to melt it all. Whisk everything until completely smooth.
3. Yup, it’s that easy. When it’s cold, it’s firm yet soft. When it’s warm, it’s liquid. Very versatile. (You can store this in the fridge for up to a week, but it will firm up. To bring it back to its liquid splendor, microwave it in 30-second intervals and stir between each nuking until it’s saucy.)
4. Wait until the sauce cools to lukewarm (so it doesn’t melt down the mousse), and carefully pour sauce onto the tops of your molds. It’s going to start setting almost immediately on contact from the cold, so work fast. Back into the freezer they go for at least 4 hours, to fully set. Once set, if you plan to keep them frozen for a while, be sure to wrap the tray very well to keep the cakes from absorbing strange freezer flavors.

To serve:

1. The day you want to serve them, you can unmold the number you need. They come out of the rings more cleanly when frozen. First, roll them around in the palms of your hands for a minutes. The heat helps release them.
2. Then treat them like a push-pop, and gently press them out. They have a tendancy to slip out and land with a thud on your tray, so go slowly.
3. Keep them uncovered in the fridge while they defrost. It probably takes a couple of hours to defrost something of this size. If you made a big cake, you may need another hour or two.
4. Don’t let them sit in the fridge for more than a day. The longer a gelatin-based dessert sits in the fridge, the more rubbery it becomes.
5. Right when you’re ready to serve, warm the chocolate sauce in the microwave for 30 seconds, give it a stir and pour some in your dish. Carefully place a cake in the center, handling it as little as possible to avoid getting grubby fingerprints all over it. Adorn the top and sides with some crunch pieces.

Recipe by: pastrypal.com

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