Creating Chicken Hashbrown Casserole is straightforward when you follow these easy steps:

1. Preheat Oven: Begin by preheating your oven to 350°F (175°C).
2. Mix Ingredients: In a large mixing bowl, combine the cooked, shredded chicken, frozen hashbrowns, 1 cup of shredded cheddar cheese, cream of chicken soup, sour cream, milk, garlic powder, onion powder, salt, and pepper. Stir well to combine.
3. Transfer to Casserole Dish: Grease a 9×13 inch casserole dish and pour the mixture into it. Spread it evenly.
4. Add Topping: If you like a crunchy topping, mix the crushed cornflakes with melted butter and sprinkle over the casserole.
5. Bake: Place the casserole in the preheated oven and bake for 45 minutes or until heated through and golden.
6. Cool: Once baked, remove it from the oven and let it sit for about 10-15 minutes before serving. This allows the flavors to settle.
7. Serve: Enjoy your delicious Chicken Hashbrown Casserole warm!

This simple step-by-step guide will help you master this delightful dish with ease.