For the chestnut soup, finely chop shallots and sauté in hot olive oil until translucent. Pour in the vegetable soup and bring to the boil. Add chestnuts and simmer for 8 minutes until chestnuts are soft.
Remove 6 pieces of nice chestnuts from soup and set aside. Puree the rest with a blender and season with salt, pepper and lemon juice. Cut the 6 chestnuts into small cubes.
Whip the cream. Before serving, heat the soup again and pour into soup bowls.
Place 1 tablespoon of whipped cream on each and serve the chestnut soup sprinkled with the chestnut cubes.