Arrange the slices of pork loin in a shallow dish. Season with salt and pepper. Sprinkle with thyme and drizzle on some olive oil. Cover with foil and leave to marinade for 30 minutes.
Heat an ungreased pan. Place the slices of pork loin in the pan and cook for 8 minutes on each side. Place in a dish and serve right away, accompanied by a vegetable gratin.