Make gravy broth:After turkey goes into the oven, place the neck, giblets and wing tips in a 4- to 6-quart saucepan. Add 1 carrot, 1 stalk celery, 1 large onion and 2 cloves garlic, all chopped. Cover by 2 inches with 1/2 bottle white wine (inexpensive sauvignon blanc, fume blanc or pinot grigio), 2-1/2 cups (20 ounces) canned chicken broth and water as needed. Simmer, partially covered, 2 to 3 hours. Broth will reduce. Keep solids covered with a little liquid.
Starting the pan gravy: For rich-tasting pan gravy, skip additions such as Kitchen Bouquet or salt. Instead, put the turkey juices to work. Place the turkey on a platter, tent with foil and keep warm (it will be juicier for the rest). Skim fat from the pan juices.
Set roasting pan over 2 high-heat burners. Start boiling down pan juices, scraping up any browned bits with a spatula. Gradually add the strained broth, a cup at a time. After 3 to 4 cups, continue boiling and stirring until you have 2 to 3 cups of rich, deep-flavored liquid.
No lumps, great taste: As liquid simmers, take a tall glass and add to it 1 generous tablespoon of flour. Avoid lumps by using a fork to gradually beat in 1/2 to 2/3 cup cold water. Beat until there are no lumps. You’ve made a slurry.
Whisk it into the bubbling pan liquid. Keep simmering and whisking until the gravy is smooth and thick enough to lightly coat a spoon.
Taste. If you taste raw flour, simmer another minute. Season if necessary, pour into a sauceboat and serve. Leftover gravy reheats beautifully.