1. Place cooked noodles in a greased 2-quart baking dish.
2. Brown beef. Remove from skillet and drain all but 1 tablespoon of fat from skillet. Sauté the onion. Return the beef to the skillet.
3. Blend in the flour, seasoned salt and lemon pepper. Stir in the mushrooms with their liquid, green beans and tomato sauce. Spoon mixture over the noodles, spreading evenly. Sprinkle with cheese.