Source: Springfield Journal-Register

1 medium onion, chopped
2 tablespoons butter or margarine
1 tablespoon vinegar
3 tablespoons brown sugar
1 cup ketchup
3 tablespoons Worcestershire sauce
1 tablespoon dry mustard
1 cup water
1/2 cup celery, chopped
Salt and pepper to taste
1 to 1 1/2 pounds cooked, shredded pork
4-6 sandwich buns

Combine all ingredients except pork in a saucepan. Cook slowly until flavors are blended and butter is melted, about 15 minutes. Stir in pork. Serve on buns.

Makes 4-6.