This gravy will start with turkey stock. This will make good use of the neck and giblets from your turkey.
2 Tbsp olive oil
Turkey neck and giblets
2 medium carrots (chopped)
2 large celery ribs (chopped)
1 medium onion (quartered)
8 cups of water
1/2 tsp Rosemary
salt and pepper to taste
Heat oil in a stock pot over moderate heat until hot, but not smoking. Add neck and giblets; cook, turning occasionally, until golden brown, about 3 minutes. Add vegetables and cook, stirring occasionally, about 5 minutes. Add water, Rosemary, salt and pepper. Simmer, uncovered until liquid is reduced to about 5 cups; about 20 minutes.
Pour stock through a strainer into a bowl. Discard the solids.
Hint: Save all celery tops, carrot tops and peelings, and any other veggie pieces as you prep. Throw them all into the stock pot to add flavor. (Only fresh - nothing old) I like to add any tomatoes or other veggies I need to use up as well. Increase the amount of water for 4 quarts. You'll wind up with enough stock for your stuffing, green bean casserole, and gravy. Plus you'll have enough for anything else you may need to use it in.
Once your turkey is out of the oven and you're ready to make your gravy, whisk 1/2 cup of flour into one cup of the stock and set aside. Scoop 1 cup of drippings from your turkey roaster and add to the stock in your your gravy pan. Bring the stock and drippings to a slow boil. Stir flour mixture slowly into boiling stock. Stir constantly until gravy thickens. Taste and add salt and pepper if needed.