Stir together the hoisin sauce, vinegar, brown sugar, and soy sauce in a medium bowl. Dip each pork chop into the mixture, and place in a shallow baking dish.
Pour any remaining sauce over the top. Cover, and refrigerate for 30 to 60 minutes.
Preheat the oven to 350 degrees F (175 degrees C).
Bake the pork chops uncovered until the sauce has turned to a glaze and the meat is cooked through, 30 to 40 minutes.
