How to Make It
Strain the pan juices into a fat separator or bowl. Let stand for 10 minutes. Skim and discard the fat from the surface; set the juices aside.
Place the empty roasting pan over two burners over medium-high heat. Add the wine and cook, stirring and scraping to dissolve any bits stuck to the pan, for 2 minutes. Add the butter and melt. Sprinkle with the flour and cook, stirring constantly, until lightly golden, about 3 minutes. Still stirring, slowly add first the broth, then 1 cup of the reserved juices. Bring to a boil. Reduce heat and simmer gently until the gravy has thickened, 5 to 10 minutes. Remove from heat and season with the salt and pepper. Strain just before serving.
If your gravy is too thin: Whisk 2 teaspoons cornstarch into 2 teaspoons cold water, or combine 1 tablespoon room-temperature butter with 1 tablespoon flour to form a paste. Whisk into 4 to 5 cups of barely simmering gravy and cook, stirring constantly, until the gravy thickens.
If your gravy is too thick: Add more of the reserved pan juices or warmed turkey or chicken broth, 1 tablespoon at a time. Or try a splash of a flavorful fortified wine, such as Madeira or sherry.