Sprinkle the chops with salt and ground black pepper.
In a large skillet, heat oil over medium-high heat. Add chops, cook about 4 minutes or until brown, turning once. Remove the chops, reserving drippings in skillet.
Add onions to the reserved drippings. Cook over medium heat for 4 to 5 minutes or until crisp tender, stirring occasionally. Reduce heat to medium-low.
Sprinkle onion with about half of the marjoram. Place chops on top of onion in skillet. Spread the chops with mustard. Arrange apple wedges around the chops; sprinkle the chops and apple with the remaining marjoram.
Cover and cook for 5 to 6 minutes or until pork juices run clear. Serve the chops with apple wedges, onion and pan juices.