My grandmother was a great cook, and I watched and remembered many things, but I never figured out gravy."
When my turkey is done I remove the fat and measure it according to how much gravy I want. I put back in even amounts of fat and flour, several tablespoons of each but accuracy is not important here... and cook to slightly brown the flour. Then I stir in turkey stock (simmered from gizzards and neck with celery, onion and carrot while the bird is cooking) and stir up the fond from the bottom of the pan. As you are cooking, the gravy will begin to thicken. Stir in milk to thin it to the consistency you like. The most important "secret"? Add a splash of black coffee.
Thanks. Now I remember that she did simmer the innards. The cat got them, and the broth went into the gravy.