To bake or roast a turkey, preheat the oven to 325 F. Place the turkey on a rack in a roasting pan and put it in the oven. Cook the turkey until a meat thermometer reads 180 F in the bird's thigh or 165 F in the breast.
Place the turkey on the rack with the breast facing up and tuck the wings in underneath the turkey's shoulders. Brushing or spraying the skin with vegetable or cooking oil browns the skin more attractively but isn't vital. Before putting the turkey in the oven, insert the probe of an oven-safe meat thermometer deep into the bird's breast or thigh without touching the bone.
Cooking an unstuffed turkey to a safe internal temperature takes from two to five hours in a conventional oven or 1 1/2 to 3 1/2 hours in a convection oven, depending on the size of the bird, the type of roasting pan and the rack positioning. The United States Department of Agriculture recommends cooking turkeys without stuffing to reduce the risk of food poisoning. To prevent overcooking, place a loose tent of aluminum foil over the breast and drumsticks about two-thirds of the way through the cooking time. After removing the turkey from the oven, allow it to stand 20 minutes before carving.