Kansas City Barbecue Sauce Recipe

Ingredients

• 2 tablespoons butter
• 1 cup finely chopped white onion
• 3 garlic cloves, minced
• 2 cups ketchup
• 1/2 cup packed brown sugar
• 1/3 cup molasses
• 1/4 cup cider vinegar
• 2 tablespoons yellow mustard
• 2 tablespoons chili powder
• 1 teaspoon salt, divided
• 1/2 tablespoon coarsely ground pepper
• 1/4 teaspoon cayenne pepper