Roast Turkey

For Turkey Broth: bring water and gizzard, neck & heart to boil in a heavy large saucepan. Reduce heat and simmer until liquid is reduced to 3 cups, about 1 hour. Strain. (Can be prepared 1 day ahead. Cover and refrigerate.) Roast Turkey Preheat oven to 450(F) degrees. Butter 8 cup baking dish. Rinse turkey inside and out. Pat dry. Fill neck-end cavity with some of chestnut stuffing. Fill main cavity loosely with some of stuffing. Sew main cavity closed. Tie legs together. Tuck wings under body. Place turkey breast side up on rack in large roasting pan. Rub butter or margarine over turkey. Transfer remaining stuffing to prepared dish. Cover stuffing with foil. Roast turkey 45 minutes. Reduce oven temperature to 350 degrees. Roast turkey until meat thermometer inserted in thickest part of thigh registers 175F, basting turkey frequently with pan drippings, about 2 hours 15 minutes. (Place stuffing in covered baking dish in oven during last 45 minutes.) Transfer turkey to platter, reserving drippings in roasting pan for gravy. Tent turkey with foil to keep warm and let stand 20 minutes while preparing gravy. Gravy: Scrape bottom of roasting pan to loosen any browned bits. Pour contents of pan into large measuring cup. Let stand until fat rises to the surface. Spoon off fat from measuring cup, reserving 1/2 cup. Add 3 cups turkey broth to pan drippings in measuring cup. Pour reserved 1/2 cup fat into heavy skillet. Cook fat over medium heat until hot. Add flour and cook until golden brown, stirring constantly, about 4 minutes. Add broth mixture and bring to boil, stirring constantly. Cook until sauce thickens, stirring frequently, about 10 minutes. Add thyme. Season with salt and pepper.