3 lb. hamburger
1 1/2 c. onion
1/3 c. vinegar
1/3 c. Worcestershire sauce
1 1/2 c. catsup
1/2 c. brown sugar
1/3 c. prepared mustard
1/3 c. butter

Brown hamburger and onions. Add remaining ingredients. Simmer 1 hour before serving. Top with Velveeta cheese if desired.