Greek Chicken Phyllo Pie

1 broiler-fryer, cut up
5 cups water
1 onion, chopped
1 stalk celery, cut into 1-inch pieces (optional)
1 bay leaf
1 teaspoon salt
1/4 cup butter or margarine
1/3 cup all-purpose flour
3 large eggs, lightly beaten
1/4 cup grated Romano or Parmesan cheese
1/2 teaspoon salt
1/4 teaspoon ground white pepper
1/4 teaspoon black pepper
1/8 teaspoon ground nutmeg
1 (17 ounce) package commercial frozen phyllo pastry, thawed
1 cup melted butter or margarine
Celery leaves (for garnish)

Combine first 6 ingredients in a Dutch oven. Bring to a boil; cover, reduce heat, and simmer 40 minutes or until tender. Remove chicken, and cool slightly. Bone chicken, cutting meat into bite-size pieces; set aside. Remove and discard celery and bay leaf, reserving 3 cups broth and onion mixture; set aside.

Melt butter in a Dutch oven over low heat; add flour, stirring until smooth. Cook 1 minute, stirring constantly. Gradually add reserved broth mixture; cook over medium heat, stirring constantly, until thickened. Gradually stir about one-fourth of hot mixture into eggs; add to remaining hot mixture, stirring constantly. Add cheese and next 4 ingredients. Cook over low heat, stirring constantly, about 3 minutes or until thickened. Add chick and set aside.

Unfold phyllo, and cut the stack of sheets in half crosswise. Trim each half to a 13 x 9-inch rectangle. Cover with a slightly damp towel to prevent pastry from drying out.

Coat bottom and sides of a 13 x 9-inch pan with melted butter or margarine. Layer 15 trimmed phyllo sheets in pan, brushing each with melted butter or margarine. Spread half of chicken mixture evenly over phyllo. Top with 12 additional trimmed phyllo sheets, brushing each with melted butter or margarine. Spread remaining chicken mixture over phyllo; top mixture with remaining trimmed phyllo sheets, brushing each with melted butter or margarine.

With a sharp knife, cut through only the top layer of phyllo to make 12 servings. Bake, uncovered, on lowest rack in oven at 375 degrees F for 1 hour.

Let stand 10 minutes. Garnish with celery leaves, if desired.

Yields 12 servings.