Delicious Chicken Casserole

Preheat oven to 350 degrees F (175 degrees C).
Bring to a boil the chicken breasts, celery, 1/2 teaspoon salt, 1/8 teaspoon pepper, and enough water to cover. Cover, reduce heat to medium low; simmer for 35 minutes. Drain, reserving 1 cup liquid. Cool chicken, remove meat from bones, and cut into bite-size pieces.
In a large bowl, stir together sour cream, soup, broth, celery salt, onion powder, garlic powder, and salt and pepper to taste. Mix in cooked rice and chicken. Spoon mixture into a 9x13 inch casserole dish. In a resealable bag, shake together crushed crackers and melted butter. Sprinkle crackers over the top.
Bake in preheated oven for 30 to 35 minutes.