Ingredients:

  Amount  Measure       Ingredient -- Preparation Method
--------  ------------  --------------------------------
     1/2  stick         butter
     1/4  cup           minced onion
   1 1/4  cups          cider vinegar
   1 1/4  cups          ketchup
     3/4  cup           brown sugar
   1      teaspoon      Worcestershire sauce
     1/4  teaspoon      cayenne pepper
                        salt and pepper to taste

Preparation:

Sauté onion in butter. Add rest of ingredients and simmer 30 minutes. Use on pork smoked with vinegar based mop.