2. Finely grate 1 tablespoon of zest from the lemon, mix it with half of the rosemary and set aside.
3. Cut the lemon into quarters. Rub the entire chicken and the cavity with one of the lemon quarters, then discard it. Season the chicken with salt and pepper.
4. Rub the cavity of the bird with the lemon zest mixture. Place the chicken on a rack in a roasting pan and stuff it with the remaining lemon and the onion and apple quarters.
5. In a small bowl, combine the apple cider and the remaining rosemary. Pour half of this over the chicken and place it in the oven. Baste with the remaining cider mixture and the liquid in the pan at least 4 times during cooking. Roast until the juices run clear when the thigh is pierced with a knife, about 1 1/2 hours.
6. Transfer to a serving platter and let rest 10 to 15 minutes before carving.