Mold of Chicken with Mushroom Sauce

2 3/4 to 3-pound chickens
2 stalks celery with leaves
7 or 8 peppercorns
3 cups water
1 teaspoon salt
1/4 teaspoon black pepper
1/2 cup skimmed reserved broth
3 beaten egg yolks
1/4 cup fine, white bread crumbs
3 egg whites
1 bunch watercress
1 (10-inch) ring mold

The chicken for a ring mold should be one of good flavor. A Perdue fowl or roasting chicken or one from a good organic food shop is the best I have found. Cook the birds whole. This will help to preserve the flavor. Place them in a pot with celery, leaves included, and the peppercorns. Add 3 cups of water. Cover and set on a medium-high burner to start cooking. When simmering begins, turn the burner very low and simmer for 2 hours without allowing the pot to boil. I find that the broth has a much better taste if prevented from boiling. When the chicken is well cooked and tender, drain away the broth and set aside to cool. Skim the far off and reserve. Cool the chicken a bit, remove the skin, and cut into fine pieces by hand while still warm. There should be enough to fill a quart measure. It is better to do the chopping by hand instead of using a food chopper. The meat will further crumble by mixing. Place the dried meat into a mixing bowl. Sprinkle in salt, pepper, 1/2 cup of reserved broth, 3 tablespoons of fat skimmed from the broth, and the beaten egg yolks. Mix well, and then sprinkle in the bread crumbs, made from rubbing fresh slices of white bread against a grater. Beat the egg whites until stiff but not dry, then fold them into the chicken. Spoon the mixture into a well-buttered 10-inch ring mold. Place the mold in a pan of hot water and set to cook in a pre-heated 350¡ oven for 45 minutes. When finished, remove from the oven and allow to rest for 10 minutes before unmolding. Turn out onto a hot platter, fill the center with sprigs of watercress, and garnish the platter with same.