1In large mixing bowl mix together ground beef, dry onion soup mix, bread crumbs, eggs , milk, parsley flakes, garlic powder and salt and pepper.
Form walnut size meatballs .. in heated oiled skillet fry meat balls until browned on all sides. Remove meat balls from pan .. remove most but not all grease (leaving meat drippings in pan) add flour and stir constantly until blended/smooth and slowly add water to desired thickness, salt/pepper to taste ... heat until gravy is a smooth texture,you may need to add a bit more of water, you judge ... finally add drained can of mushrooms, cook a minute or two .. return meat balls to gravy , cook on low for 5 minutes.
Serve in shaffing dish or as a main dish with mashed potatoes
2Variation: put a small piece of cheese in center of meat ball when forming.