Preheat the oven to 425 degrees F (220 degrees C).
Whisk onion, ketchup, vinegar, honey, brown sugar, Worcestershire sauce, mustard, and cayenne pepper together in a bowl until barbeque sauce is smooth.
Place pork chops on a baking sheet and season with salt and pepper. Top each pork chop with 2 tablespoons of barbeque sauce.
Bake in the preheated oven until pork chops are cooked through, about 30 minutes. An instant-read thermometer inserted into the center should read at least 145 degrees F (63 degrees C).
