Tangy Barbecue Sauce

2 tablespoons butter or margarine
3 tablespoons chopped onion
1/2 cup chopped celery
2 tablespoons brown sugar
2 tablespoons vinegar
1-tablespoon Worcestershire sauce
1/4 cup lemon juice
1-cup catsup
1 teaspoon dry mustard
Dash pepper

Melt butter in a skillet and cook onion and celery until tender. Add the remaining
ingredients and cook to blend flavors, 15 to 20 minutes. Makes about 1-1/2 cups.