Soak gelatine in a little cold water, crumble milk chocolate and melt in the microwave or in a bain-marie. Squeeze out the gelatine and dissolve in the chocolate. Mix the puree with the liquid chocolate.
Whip half of the cream until stiff, add sugar and stir into the chestnut puree.
Allow the mixture to set in the refrigerator for 2 – 3 hours. Sprinkle the cocoa powder on plates.
Whip the remaining cream with the vanilla sugar until semi-stiff and spread it in the middle of the plates.
Use a spoon to make small balls of the chestnut cream and arrange on the cream.