Sprinkle chops with salt and pepper. Heat oil in a large nonstick skillet coated with cooking spray over medium-high heat until hot. Add chops and onions; cook for 4 minutes on each side or until lightly browned. Scrape the seeds from vanilla bean; add seeds, bean, and wine to pan, scraping pan to loosen browned bits. Cover, reduce heat, and simmer 20 minutes or until pork and onions are tender. Remove pork and onions from pan with a slotted spoon; keep warm.
Combine the brown sugar, balsamic vinegar, and cornstarch in a small bowl. Add to wine mixture in pan, and bring mixture to a boil. Cook the mixture for 1 minute, stirring constantly. Discard the vanilla bean. Serve the vanilla sauce with the pork chops and onions.