Creamy Chestnut Soup

Adjust oven rack to middle position and heat oven to 400 degrees F.

With a small, sharp knife, slit the outer shell of each chestnut, put them in a shallow baking pan, and roast until tender, 15 to 20 minutes.

Peel off the outer shells and inner skins while still warm. Reheat if the chestnuts cool and become difficult to peel.

Peel and thinly slice the onion and the shallots. Thinly slice the celery tops and leaves (reserve ribs for another use). Julienne the prosciutto. Wrap and refrigerate 2 tablespoons prosciutto for garnish.

Heat 2 tablespoons of the butter in an 8-quart soup kettle and saute, the onion, shallots and remaining prosciutto over medium heat until softened, about 5 minutes.

In a large saucepan, bring 6 cups of the chicken stock to a boil. Stir the hot chicken stock into the shallot mixture along with the chestnuts, celery, fennel seeds, bay leaf, and 1/2 teaspoon salt.

Bring the mixture to a boil and skim. Reduce the heat and simmer covered for 45 minutes. Remove and set aside 16 chestnuts for garnish.

Continue simmering until remaining chestnuts are very tender, about 45 minutes longer.

Remove soup from heat, discard the bay leaf, and set aside to cool 15 minutes. Pour the soup into the work bowl of a food processor fitted with a metal blade, or into a blender. Puree, then strain through a fine sieve or tamis.

Reheat the soup over low heat. Bring the remaining 4 cups of chicken stock to a boil in a saucepan and stir in enough stock (3 to 4 cups) to thin soup to the consistency of thick cream.

Bring the soup to a boil, stir in the heavy cream, 1/2 teaspoon white pepper, and salt to taste. Cover and keep warm over low heat.

For the garnish, put the dried cepes in a small saucepan with enough water to cover and simmer until tender, 3 to 4 minutes. Drain and cut into 1/4-inch dice.

Heat the remaining tablespoon butter in a medium nonstick skillet and saute the cepes, the reserved chestnuts, and the reserved prosciutto until crisp, 3 to 4 minutes. Remove pan from heat and stir in the parsley.

Divide the garnish evenly among individual soup bowls and ladle hot soup over it. Serve immediately.