Preheat your oven to 350°F (175°C).
In a large mixing bowl, combine the shredded chicken, cream of chicken soup, sour cream, and mixed vegetables.
Add garlic powder, onion powder, and black pepper to the mixture. Stir until well combined.
Transfer the chicken mixture into a greased 9x13-inch baking dish.
Spread the mixture evenly in the dish.
In a separate bowl, combine the crushed Ritz crackers and melted butter.
Sprinkle the buttery cracker mixture evenly over the chicken.
Top with grated cheese for added flavor.
Bake in the preheated oven for 30 minutes, or until bubbly and golden brown.
Let it cool for a few minutes before serving.