Season both sides of pork chops with salt and pepper. Heat a large skillet over medium-high heat. Add olive oil. Add pork chops, reduce heat to medium and cook, turning once, until nicely browned and juices run clear, about 10 minutes. Transfer to a plate and tent with foil to keep warm.
Pour off extra grease from pan. Put onion in same pan and cook for 3 minutes. Stir in wine and thyme. Increase heat to medium-high and bring liquid to a boil. Reduce heat and simmer until reduced by half, about 3 minutes. Stir in sugar. Add butter and any accumulated juices from pork and stir to combine.
Serve pork chops with onions and pan juices spooned on top. Serve with a green vegetable and bread.