Before starting this Chocolate Charlotte recipe, make sure you have organised all the necessary ingredients.
In a casserole, pour the sugar and a little water (5 or 10 cl). Bring to a boil.
In the meantime, crack the whole eggs in the stand mixer stand mixer recipient.
When the boiling intensity starts reducing, check the temperature with a laser thermometer. When the temperature is 121°C, take the pan away from the heat.
Beat the whole eggs in the stand mixer, then reduce the speed and gradually add the boiling sugar.
Increase to maximum speed and continue beating until cooled down completely.
At this stage, the preparation should have at least doubled in volume (this is called 'pâte à bombe'). Set aside.
In the meantime: Melt the dark chocolate over a bain-marie.
Once the pistoles have melted completely, remove from the bain-marie and set aside.
Beat the cold whipping cream to obtain a whipped cream. Set aside.
Add the melted chocolate to the pâte à bombe.
Combine gently with a rubber spatula...
... until the chocolate is incorporated evenly.
The consistency and colour should be homogeneous: make sure no solid bits remain.
Add the chocolate preparation to the cold whipped cream.
Combine all the ingredients...
... until homogeneous. This dark chocolate mousse has a solid consistency and makes a perfect filling for cakes.
Combine the cane sugar syrup and rum (or Grand-Marnier). Steep the biscuits in the syrup.
Place the sponge fingers vertically to line the sides of a charlotte mould.
The biscuits should stand next to each other and the inside surface of the mould should be completely lined.
Cut a disk of greaseproof paper to the same diameter as the charlotte mould.
Place the paper disk at the bottom of the mould. This will ensure an easier release.
Arrange the layout of the biscuits if needed.
Scoop the chocolate mousse into a piping bag.
Fill the bottom of the mould with chocolate mousse, up to 1 or 2 cm. Now that the base of the biscuits is held by the mousse, finish arranging them so they are perfectly lined up.
Continue filling the cavity with the chocolate mousse...
... up to the rim. Place the piping bag containing the rest of the chocolate mousse in the fridge. You will need it later for decorating the cake.
Place the sponge cake disk on top of the chocolate mousse.
Press gently to remove any air pockets from the mousse. If you wish, you can brush some syrup on the sponge cake disk. Cover the mould with cling film and refrigerate overnight. If possible, it is preferable preparing the charlotte the day before. Otherwise, refrigerate for at least 2 hours before releasing from the mould.
The next day: Flip the mould onto a baking sheet.
Gently remove the mould, sliding it upwards.
The charlotte should be set and the biscuits should remain intact.
Remove the disk of greaseproof paper.
To garnish the surface of the charlotte, pipe swirls of chocolate mousse with the remaining quantity stored in the fridge.
Repeat the operation...
until the whole surface is covered.
Finish by sprinkling white chocolate shavings on top.