Directions

1. In a large pot boil the chicken with the onion, celery and bay leaves until done. Let chicken cool until you can handle it. Remove chicken meat from the bones and cut into small pieces.
2. Preheat oven to 375 degrees F (190 degrees C).
3. In a saucepan over medium heat melt the butter. Stir in the flour and cook for about 1 minute. Slowly stir in the cold milk and chicken stock and cook mixture until thick. Stir in the cheese.
4. In a large bowl combine the chicken, rice and mushrooms together. Stir in the cheese sauce and season with salt and pepper. Place mixture in a 1 1/2 quart casserole dish.
5. Bake at 375 degrees F (190 degrees C) for about 30 minutes or until bubbly.