1 pkg. hash browns with red & green bell peppers
1 can cream of mushroom soup
2 tbsp. butter
4 oz. sour cream
1 can mushrooms
1 can French fried onions

Mix all ingredients, except French fried onions, together. Pour in 1 quart baking dish. Bake at 350 degrees for 40 minutes. Take out and put French fried onions on top and brown for about 5 more minutes.