Use this sauce for Southern Grilled Chicken with Macaroni Salad.
In a medium saucepan, melt butter over medium heat. Add onion and garlic; season with salt and pepper. Cook until soft, 2 to 3 minutes. Add ketchup, vinegar, sugar, Worcestershire, hot sauce, and cayenne. Bring to a simmer. Cook, stirring occasionally, until slightly thick, about 5 minutes. Set aside.