Western South Carolina-style barbecue sauce

From Cook's Illustrated

Makes 2 cups. Published July 1, 1997.

Ingredients

1	tablespoon vegetable oil
1/2	medium onion , minced
2	medium cloves garlic , minced
1/2	cup cider vinegar
1/2	cup Worcestershire sauce
1	tablespoon dry mustard
1	tablespoon dark brown sugar
1	tablespoon paprika
1	teaspoon table salt
1	teaspoon cayenne pepper
1	cup ketchup

Instructions

Heat oil in 2-quart saucepan over medium heat. Add onion and garlic; sauté until softened, 4 to 5 minutes. Stir in all the remaining ingredients except ketchup; bring to boil. Reduce heat to low, then add ketchup. Cook, stirring occasionally, until thickened, about 15 minutes.