Preheat your oven to 385°F and lightly grease a 9x13-inch baking dish.
In a large mixing bowl, combine shredded rotisserie chicken, cream of chicken soup, sour cream, frozen mixed vegetables, garlic powder, onion powder, salt, and black pepper. Mix until everything is well coated.
Transfer the chicken mixture to the prepared baking dish and spread it into an even layer.
In a separate bowl, combine the stuffing mix with the chicken broth and stir until the broth is absorbed.
Evenly spread the stuffing mixture over the chicken mixture.
Top the stuffing with sliced butter.
Bake uncovered at 385°F for 30 minutes, or until the casserole is hot, bubbly, and the stuffing is lightly golden.
Let the casserole rest for 5 minutes before serving. Garnish with fresh parsley if desired and enjoy.
