Preheat the oven to 350 degrees F.
Take the giblets out of the turkey and wash the turkey inside and out. Remove any excess fat and leftover pinfeathers and pat the outside dry. Place the turkey in a large roasting pan. Liberally salt and pepper the inside of the turkey cavity. Stuff the cavity with the thyme, lemon, onion, quartered, and the garlic. Brush the outside of the turkey with the butter and sprinkle with salt and pepper. Tie the legs together with string and tuck the wing tips under the body of the turkey.
Roast the turkey for 2 1/2 hours, basting from time to time with pan juices, until the juices run clear when you cut between the leg and the thigh. Remove the turkey to a cutting board and cover with foil; let it rest for 20 minutes. Slice the turkey and serve hot.
Recipe courtesy of Barefoot Contessa Parties!, 2001, All Rights Reserved