Four delicious layers of mousse, custard, and cream, and a fantastic disk of chocolate on top. Really delicious, and really simple to make - just how every cake should be. The Nutella base is quickly turning into my new favourite; I have to admit. And the lovely mix of coffee mousse, rum, Mascarpone custard... Bliss in a miniature cake form. You might notice a different way of building layers in this recipe.
The main reason behind not spreading the mousse or custard on the previous layer is to keep its airy texture intact. If you spread it, you risk losing some of the tiny air pockets in the mousse. You can try piping it on for a neater final look, but I still stand by this method, as I found it works best. To slice the cake, you will need a heated knife, to cut through the chocolate disk. Pour hot water in a jug, place a thin blade knife in the water, dry if off, then carefully slice through the disk. After that, the knife will slide through the layers very easily.
Ingredients
For the Nutella base
200 grams hazelnut wafers
2-3 tablespoons Nutella, room temperature
For the coffee Ganache mousse
100 grams cooking chocolate
120 ml double cream
1 teaspoon instant espresso powder
For the Mascarpone custard
50 grams Mascarpone cheese, room temperature
2 tablespoons custard powder
2 tablespoons double cream
2 teaspoons dark rum
For the whipped cream layer
75 ml double cream
1 tablespoon icing sugar
1 teaspoon clear vanilla
For the chocolate disk
50 grams cooking chocolate
1 tablespoon vegetable oil
Preparation
Start by lining a small round cake pan ring (10 cm) with acetate, for an easier removal of the cake once it is ready. Make sure the acetate strip is tall enough for you to pour in three types of fillings. Once the pan is prepared, crush the wafers in a food processor, or by hand, if you want a variety of crumb sizes, pour them into a medium bowl, and add the Nutella. It should be at room temperature to make it easier to combine with the wafer crumbs. Start with two tablespoons of it, mix well, then add another tablespoon, if you wish to have a softer cake base. It will most definitely firm up in the refrigerator, so have no worries about it supporting the weight of the cake. Once the base is prepared, place the cake ring on the serving platter, and press in the wafer base. The batter will be slightly sticky, but be patient with it, and it will spread out evenly. Set the base aside and start making the fillings.
Next, make the coffee Ganache mousse. Pour the double cream in a heavy-bottomed saucepan, and let it almost come to a boil. Take another bowl, and add the chopped up chocolate. Add the coffee granules to the hot double cream, mix briefly, and pour everything over the chocolate. Let it stand for a minute or two, then mix it well with a spatula. Once it is almost at room temperature, place it in the refrigerator to help it cool down almost completely. Then take a mixer and beat the Ganache on the highest setting for a few minutes, until it becomes smooth and fluffy, like a mousse. Carefully drop the mousse by the spoonful on the base, then just gently shake the platter to evenly distribute it, and place it in the refrigerator.
To make the Mascarpone custard, add the room temperature Mascarpone into a medium bowl, add in the custard powder, and beat with an electric mixer on high until creamy and combined. Add in the double cream, and the rum, then blend it well again. Take the cake out of the refrigerator, and carefully pour in the custard over the Ganache mousse, then return to the refrigerator.
After about 30 minutes, the custard should set up. Take the double cream, pour it into a medium bowl, add in the icing sugar, and vanilla, and beat with an electric mixer on high until stiff peaks form. Pour the whipped cream over the custard in the same fashion as before, then just jiggle the cake a bit, to evenly distribute everything. Return the cake to the refrigerator for about 3 hours.
To make the chocolate disk, place the chocolate in the double boiler, and let it start melting slowly. Once it starts to melt, add in the vegetable oil, and mix really well. If you do not mix it in well enough, you might end up with streaky chocolate. Let the melted chocolate cool down a bit, then pour it over the whipped cream layer. Return the cake to the refrigerator for another 4-6 hours, and serve. © TINA VESIĆ 2017
Author's note: You can top the cake with more of the wafer crumbs, or with a drizzle of your favourite dessert sauce.
