1 (2 lb.) bag frozen hash brown potatoes
2 (10 3/4 oz.) cans potato soup
1 (8 oz.) container sour cream
1/4 tsp. garlic salt
1 sm. onion, chopped
1/2 c. Parmesan cheese
butter
1/2 c. milk
8 oz. grated sharp Cheddar cheese

Mix all ingredients together except Parmesan cheese and butter. Spread in 2 1/2 quart casserole or 9x13 inch buttered dish. Dot with pats of butter. Sprinkle top with Parmesan cheese. Bake, uncovered, 1 hour at 350 degrees.