Before starting this Mocha Cake recipe, organise the necessary ingredients for the génoise sponge cake.
For the sponge cake: Combine the eggs and sugar in a mixing bowl.
Using a hand whisk, beat the preparation over a bain-marie.
The temperature should reach roughly 40°C.
Finish beating with an electric mixer until cooled down completely. If you do not have a food mixer, you can finish beating manually. The preparation is ready when doubled in volume.
Add the sifted flour...
... and incorporate gently with a maryse spatula, working in circular motions.
Pour the preparation into a round cake pan (coated with butter and flour beforehand).
Bake at 180°C (gas 4)...
... until golden and cooked through. To check whether the sponge cake is cooked, insert the blade of a knife in the cake. When you take it out, nothing should stick to the blade.
Release the sponge cake from the mould and leave to cool on a rack.
For the coffee butter cream: Organise all the necessary ingredients.
In a mixing bowl, combine the sugar with a small amount of water.
Combine well and cook until the temperature reaches 118°C. Take the pan away from the heat. The temperature should continue to rise up to 121°C, even away from the heat. I recommend using a digital thermometer with probe. If you don't own one, simply dip a fork in the boiling sugar. If you see strings forming when you take the fork out, that means the sugar is ready.
Clarify the eggs one by one. Place the egg yolks in the stand mixer recipient and start beating at low speed. Wait until there are no more bubbles (about 30 seconds) and pour the cooked sugar along the inner side of the bowl to avoid splashes of hot sugar. The egg yolks should be at room temperature.
Once the sugar is completely combined with the egg yolks, continue beating on high speed until the preparation has cooled down completely.
When cooled down, gradually incorporate the softened butter (cut into cubes).
Continue beating vigorously until you obtain a smooth and homogeneous cream.
You can add the coffee flavour at this stage. The quantity will vary according to the desired intensity.
Combine until homogeneous and without lumps.
Assembling the cake: When the sponge cake has cooled down...
... cut it crosswise in three portions with an equal thickness.
I recommend using a serrated cake knife to avoid tearing the sponge cake.
Using a pastry brush, steep the bottom sponge cake with the syrup. Alternatively, you can use cane sugar syrup mixed with dark rum. Place the sponge cake base on a cake board to ensure an easier handling later in the recipe.
Reserve 3 to 4 big spoons of buttercream for the finish. Place 1/3 of the cream over the sponge cake base...
... and spread with a metallic cranked spatula to an even thickness.
Cover with a second disc of sponge cake.
Make sure the cake is well centred.
Steep the sponge cake disc with syrup.
Place another third of coffee cream over the cake.
Using the cranked spatula, spread into a regular layer.
Cover with the last disc of sponge cake.
Steep with syrup and cover with the last third of the coffee cream.
Spread over the surface and sides of the cake to an even thickness, making sure the finish is as clean as possible.
Using a piping bag fitted with a fluted nozzle, fill with the cream set aside earlier and pipe drops over the surface of the cake. Don't hesitate to customise this dessert with the pattern of your choice!
I made a swirl border all around the cake, then a cross pattern in the centre.
Scatter a few dark chocolate coffee beans over the surface of the cake.
Toast the flaked almonds. You can do this in the oven under the grill (but make sure they don't get burnt).
A good alternative with great results and a uniform colour is to use the microwave. Place the flaked almonds in a plate and heat in the microwave for 10 minutes at maximum power. Stir the almonds regularly. The toasted colour is perfect!
Now is the time the cake board comes handy. Lift the cake using the cake board and coat the sides of the cake with the toasted almonds (they should have cooled down first). Simply apply the almonds with your hands, they will stick to the coffee crème au beurre.
Repeat all around the cake. Reserve in the fridge until ready to serve. Enjoy this delicious dessert!