Creating this delightful Chicken and Stuffing Casserole is a straightforward process! Follow these simple steps to ensure a successful dish every time:

1. Preheat Oven: Begin by preheating your oven to 350°F (175°C).
2. Prepare Chicken: If not cooked yet, prepare your chicken. Poach or roast until fully cooked, then shred or dice.
3. Sauté Vegetables: In a skillet, melt a tablespoon of butter over medium heat. Add the diced celery and onion. Sauté until they are soft and translucent.
4. Mix Base: In a large mixing bowl, combine shredded chicken, sautéed vegetables, chicken broth, cream of chicken soup, garlic powder, onion powder, salt, and pepper. Mix until well combined.
5. Prepare Stuffing: In a separate bowl, mix the stuffing mix with the remaining melted butter and milk, stirring until evenly moistened.
6. Layer Ingredients: In a greased 9×13-inch casserole dish, spread the chicken mixture evenly.
7. Top with Stuffing: Add the stuffing mixture over the chicken layer, spreading it evenly across the top.
8. Bake: Place the casserole in the preheated oven and bake for 40-50 minutes, or until the stuffing is golden brown and crispy.
9. Cool: Remove from the oven and allow the casserole to cool for about 10-15 minutes before serving.
10. Garnish and Serve: Sprinkle with fresh parsley if desired, then serve warm.

These easy-to-follow steps will help you create a delightful Chicken and Stuffing Casserole that your family and friends will enjoy!