Ingredients

For the dough

75 grams flour
3 eggs
75 grams sugar
1/2 vanillin sachet
20 grams butter

For the mousse

200 grams dark chocolate
4 eggs
100 millilitres cream
100 grams sugar
4 tablespoons Rum
150 grams little dark chocolate disks

Preparation

For the biscuit dough, whisk the egg yolks with half of the sugar, add egg whites whisked until stiff with the remaining sugar and add to the batter flour sifted with vanillin.
    
Put it in a pastry bag with smooth nozzle and distribute on a baking tin greased with butter, shaping a continuous drawstring, from the top to the bottom, obtaining a stripe of 35 centimetres length and 6 centimetres width.
    
Bake in a preheated oven at 180°C for 25 minutes, then level dough's sides and put aside the swatches.
    
Cover a mould with aluminium and see that the dough stripe still hot sticks on the sides.
    
For the mousse, knead egg yolks with sugar.
    
Mince chocolate, let it melt with cream, add it to the batter of egg yolks, let it cool and add Rum.
    
Whisk egg whites until stiff and add them to the batter.
    
Pour half of the mousse in the mould, arrange on it the dough's pieces and cover with the remaining mousse.
    
Put it in the fridge for 3 hours.
    
Put the Biscuit on a plate and garnish the surface as you will with chocolate disks.

Formulation courtesy of DeAgostini