Make sure you pick up a package or two of necks for roasting. That way you can have a bit more volume to reduce and concentrate the flavor. My recipe is as follows;
Turkey necks 2 pkgs or approx 3 lbs
turkey wings 2 pkgs or approx 3 lbs
Onion, medium, cut in qtrs 1ea
carrots peeled, cut in 1" pieces 2ea
celery stalks, cut in 1" pieces 2ea
canola oil 1Tbsp
Rosemary, Fresh 2 branches
Thyme, fresh 2 branches
sage, fresh 1 leaf cluster
bay leaf, fresh 3ea
cloves, whole 4ea
parsley stems,fresh 12ea
Cold water to cover
Salt to taste
Pepper to taste
Place wings and neck in deep sided roasting pan. Toss onion, carrot and celery in canola oil and layer in pan with wings and necks. Place roasting pan in 400deg oven for 40 minutes. Turn wings and necks after 20 minutes. Remove from oven, place in stock pot and cover with water. Add remaining ingredients except for salt and pepper. Bring to a boil over med high flame and then reduce to slow roll after 5 minutes. Skim scum off top as it rises and continue to simmer for 3 hrs.
Remove from heat and strain through chinoise. Place strained stock in another appropriate sized stock pot and begin to reduce. Reduce to 50%of original volume. Adjust seasoning and thicken with roux to desired thickness.
Serve immediately or refrigerate and reheat for service later.
This is the exact gravy recipe I used this year and have used for the last 26. Although I add the dripping from the turkey just before serving.