Make a slash in the rounded side of each chestnut and roast in a pre- heated 400 F. oven for 5 minutes. Peel off the shell and inner skin. Peel the carrots, parsnip, onion, and garlic. Finely chop all of the vegetables, including the scallions and celery. Melt the butter in a large saucepan over medium heat. Add the vegetables and cook for five minutes, or until soft but not brown. Add the chestnuts, stock, and bouquet garni. Gently simmer the soup for 40 minutes, or until the chestnuts are very soft.
Remove the bouquet garni and puree the soup in a blender or food pro- cessor. Return the soup to the saucepan, adding the amaretto, two- thirds of the cream, and salt, pepper, cayenne pepper and nutmeg to taste; the soup should be very flavorful. If a sweeter flavor is desired, add a spoonful of brown sugar.
To serve, ladle the chestnut soup into warmed bowls. Pour a little of the remaining cream into each bowl and marble it into the soup, stirring with a skewer. Chestnut soup is extremely rich, so keep the rest of the meal simple.