Preheat oven to 450°F. Pat turkey dry and season inside and out generously with salt and pepper.
Stuff the turkey cavity with onion, garlic, rosemary, and thyme.
Tuck wings under the body and tie the legs together using kitchen twine.
Rub the skin all over with vegetable oil.
Place the turkey breast side up on a rack in a large roasting pan. Pour 2 cups of broth into the bottom of the pan.
Roast turkey for 30 minutes, then reduce oven to 350°F. Continue to roast, basting every 30–45 minutes with pan juices and rotating the pan occasionally.
Add more broth to the pan as needed to keep the drippings from burning.
Roast until an instant-read thermometer inserted into the thickest part of the thigh registers 165°F, about 2½ to 3 hours total.
Transfer turkey to a carving board and let rest at least 30 minutes before carving.