Meanwhile, in a large skillet, brown your ground beef leaving it in bigger chunks. Drain off any excess grease.
Sprinkle the flour over the ground beef and cook for a couple of minutes. Add in your beef broth and pkg of stew seasoning.
Bring to a boil. Add in you celery, carrots, potato, and onion. Allow to simmer for about 5 minutes.
Mix the cooked noodles with the beef mixture.
Pour beef stew / noodle mixture into a 9×13 casserole dish and cover with foil. Bake at 350 degrees for 15 minutes. Uncover and sprinkle crispy fried onions on top. Bake uncovered for 5 minutes. Serves 6-8.