1. Season pork chops with salt and pepper. In a nonstick skillet over medium-high heat, warm olive oil. Add onions and cook, stirring, until softened and golden, about 5 minutes. Push onions to edges of skillet and add chops. Cook, turning once, until browned, about 6 minutes total.
2. Sprinkle sage over chops and pour cider into pan. Bring to a boil, cover, reduce heat to medium-low and simmer until chops are cooked through, 8 to 10 minutes. Remove chops from pan, raise heat to high, and boil sauce until reduced and thickened, 2 to 3 minutes. Pour sauce and onions over chops and serve.