Preheat oven to 450°F (230°C). Chop giblets and set aside. Season turkey inside and out with salt and pepper. Place on a rack in a roasting pan. Carefully lift breast skin by slipping your fingers under it and disengaging it from the meat. Spread butter over the meat and reposition the skin. Roast for 30 minutes, then scatter giblets around turkey. Reduce heat to 350°F (180°C) and roast for 3 hours, until a thermometer inserted in the thigh registers 165°F (74°C). Baste occasionally with pan drippings during the last 2 hours. Remove from oven, strain giblets out of pan drippings and reserve. Let turkey rest for 20 minutes before carving.

Meanwhile, prepare the stuffing: In a large skillet, melt butter over medium heat. Sauté celery and onion until tender. Add apple, sage, chervil, thyme, rosemary and nutmeg; sauté for 3 minutes. Add bread cubes, broth and giblets; mix to moisten. Season with salt and pepper. Just before serving, stir ½ cup (125 mL) turkey drippings into stuffing and reheat. Serve turkey with stuffing.