1 lb. ground beef
1 c. celery, diced
1/2 c. onion, diced
1 tbsp. brown sugar
2 tbsp. vinegar
1/2 tsp. dry mustard or 1 1/2 tsp. prepared mustard
3/4 c. ketchup
2 tbsp. flour
6 hamburger buns

Brown ground beef, celery and onions; add remaining ingredients and reduce heat. Simmer 20 minutes. Serve on hamburger buns.