1 lb. Ground Beef
medium onion, chopped
2 tbsp. all-purpose flour
1/2 tsp. garlic salt
1/4 tsp. pepper
4 oz. can mushrooms, drained
1 (10 3/4 oz.) Cream of Mushroom soup
8 oz. sour cream

Cook ground beef and onion in a large skillet until meat is browned; drain. Stir in flour and next 3 ingredients; cook and stir 1 minute. Stir in soup. Simmer 10 minutes, stirring occasionally. Add sour cream and heat thoroughly. Serve over noodles.