2/3 c. chopped onions
3 tbsp. vinegar
1 1/2 tbsp. prepared mustard
1 1/3 c. catsup
2 tbsp. butter
1 1/2 tbsp. Worcestershire sauce
1/4 c. brown sugar
1 c. water or beef broth
1 qt. shredded cooked beef

Saute onion in butter. Add remaining sauce ingredients. Simmer. Add beef and gently simmer for 45-60 minutes or until mixture thickens by evaporating liquid.