Once your turkey is fully cooked, tilt it so the juices drain into roasting pan, then transfer turkey to a platter, reserving the juices in the roasting pan. Let the turkey rest in a warm place loosely covered for 30 minutes.
Strain the juices into a container then skim off and discard fat. If using a fat separator, strain the juices into the separator and let stand until fat rises to top. Pour the juices from separator into a container.
Place the roasting pan on a burner over medium high heat, add wine or stock and deglaze, stirring and scraping up brown bits. Strain into container with other juices.
Melt butter in a sauce pan and add flour. Cook over medium heat, stirring constantly for about 3-4 minutes.
Add deglazed juices and stock, and bring to a simmer while whisking continuously. Season with salt and pepper.