Preheat your oven to 350°F (175°C) and grease a 9x13-inch baking dish with butter or cooking spray.
In a large bowl, mix together shredded chicken, both cans of soup, sour cream, milk, onion powder, garlic powder, thyme, salt, and pepper. Stir until smooth and well combined.
Spread the chicken mixture evenly in the prepared baking dish.
In another bowl, combine the stuffing mix with melted butter and chicken broth. Stir well and spread it evenly over the chicken layer. Optionally, sprinkle shredded cheddar cheese on top.
Bake uncovered for 35-40 minutes until the top is golden brown and bubbling.
Let the casserole rest for 5-10 minutes before serving.
