Turkey Gravy

For each 2 cups gravy desired
3 tbsp fat
3 tbsp all-purpose flour
2 to 3 cups of liquid (depending on how thick you want your gravy)
salt and pepper to taste

What liquid should I use?

Delicious gravy comes from making broth from the giblets. Even if these parts gross you out, make the broth. You can always throw away the giblets once they’ve been boiled.
Also, you can save some of the water from the boiled potatoes and use it in the gravy.

Make some broth:
 
A whole raw turkey is usually packaged with the giblets sealed in a bag in the body cavity. Giblets are those extra parts of the turkey you do not roast: the heart, liver, gizzard (a part of the turkey's stomach), and neck.

Cover the giblets, and neck bones with approximately 4 cups water in a large pot. If you’ve got it handy, add a stalk of chopped celery, a carrot, some parsley, and a chopped onion (with its peel as the onion skin gives the broth a golden color). 

Bring to a boil and then reduce heat and simmer 1 1/2 hours.
Strain and reserve liquid for gravy.  Feed the other bits to the cat or the dog (but not the neck bones - because they could choke).

Make a slurry so that you don’t get lumps in your gravy.
 
In a container with a tight fitting lid, (i.e. pasta sauce jar) shake together the flour needed and about 2 cups cool water. Really shake it. Shake it til there are no lumps.

Adding this thickened slurry (flour mixture) to the reserved pan juices helps to prevent lumps from forming when making your gravy. (I always make a little extra of this flour/water mixture just in case I need it.) 

Make the gravy
 
After you have removed the turkey from the oven and set it aside to rest, place roasting pan (with the drippings and fat) on the stove at medium heat. (always make the gravy in the same roasting pan you used to roast the turkey). Stir to scrape up the brown bits from the bottom of the pan.
 
Once the liquid, drippings, and the fat in the roasting pan are lightly bubbling, slowly add the slurry mixture to the gravy pan, stirring constantly with a whisk.
 
When the mixture starts to thicken, stop adding the remaining flour mixture. 

If it doesn’t seem to be thickening, add more slurry. You may not need to use the the entire flour mixture depending on how much or little drippings were in the pan. If lumps do develop, you should be able to use a wire whisk to remove them.
 
Once the slurry mixture is whisked into the gravy, if the gravy seems too thick, just whisk in some potato water or broth, a little at a time until desired consistency is reached.
 
Simmer gently about 10 minutes to cook the flour all the way through (undercooked flour doesn't taste very nice). Add salt and pepper to taste.