Slow & Easy Baby Back Ribs

Ingredients (13)

• 4 pounds pork baby back ribs, cut into 2-rib portions
• 1 medium onion, chopped
• 1/2 cup ketchup
• 1/4 cup packed brown sugar
• 1/4 cup cider vinegar
• 1/4 cup tomato paste or tomato sauce
• 2 tablespoons paprika
• 2 tablespoons Worcestershire sauce
• 1 tablespoon prepared mustard
• 1 teaspoon salt
• 1/4 teaspoon pepper
• 2 tablespoons cornstarch
• 2 tablespoons cold water