Preheat oven to 350 degrees.
Spray a 9x13 baking dish or pan with non-stick cooking spray. Add frozen cubed hash brown potatoes and melted butter.
In a large mixing bowl, add sour cream, shredded sharp cheddar, onion powdered, garlic powder, salt and cream of chicken soup and mix until well combined.
Add mixture evenly to the top of your frozen potatoes in you casserole dish. Top with additional shredded cheese, if desired.
Place in the oven and bake for 20 minutes. When 20 minutes have passed, add crushed cornflakes and bake for an additional 20-25 minutes. Add any additional salt and pepper, to taste.
Serve immediately and enjoy!