The Best One-Bowl Hash Brown Potato Casserole

Source: http://www.food.com/recipe/the-best-one-bowl-hash-brown-potato-casserole-78853

1 Onion, Chopped
1 Red Pepper, Chopped
1 (4 oz) Can Mushrooms, Drained
1 (16 oz) PKG Cubed Ham, Drained
1 (10 oz) Can Cream of Mushroom Soup
3/4 C Milk
3/4 C Sour Cream
5 T Melted Butter
1 t Seasoned Salt
1 t Pepper
2 t Garlic Powder
3/4 C Grated Parmesan Cheese, Divided
2 C Grated Cheddar Cheese
2LB Frozen Hash Browns, Thawed and Drained
Additional Cheddar Cheese, Optional

Saute onion, pepper, mushrooms, and ham until vegetables are tender.

Preheat oven to 350F.

Meanwhile, in a large bowl combine soup, milk, sour cream, and butter. Mix well. Add seasoned salt, pepper, garlic powder, 1/4 C Parmesan, and cheddar. Mix well. Add vegetables. Mix well. Add Hash browns. Mix well.

Transfer mixture to a LARGE lasagna pan. Sprinkle 1/2 C Parmesan cheese over top. Bake for 40 minutes. Add additional cheddar cheese on top if desired. Return to oven and bake for additional 5 minutes to melt cheese.