The turkey broth is started right after the turkey is prepared for cooking; at least one hour prior to when the gravy is made.
To a medium size pot, add water (about ¾’s full) and salt. Bring to a boil.
To the pot, add the giblets (except for the liver). Turn the heat down to low and let simmer for an hour, until the giblets are fully cooked. As it's cooking keep an eye on the water level. When the water level decreases, add hot water to the pot to fill it back up to about ¾’s full.
After the giblets are cooked, remove them from the pot (discard if desired).
Carefully pour the broth through a fine mesh strainer and into a large heat-proof pouring measuring cup or bowl.
Set aside 1/4 cup broth and chill in the refrigerator (for use when making the cornstarch slurry).
There should be at least 2 cups of broth remaining (if not, add water to the broth to equal 2 cups in total). Set the remaining broth aside (if making this ahead of time, store in the refrigerator).