In a saucepan large enough to accommodate the amount of gravy you’re making, melt the butter or heat the turkey drippings. Add 1/4 cup of the toasted flour and whisk it into the fat. When the flour mixture bubbles and spreads, add 3 cups of stock and whisk it in.
Let the stock and flour mix bubble together. The mixture will be quite thin. Now, dust the flour on top of the growing gravy one tablespoon at a time and whisk it in. It will look lumpy at first, but as you whisk vigorously, it dissolve. Add the flour until it reaches your desired consistency.
Season with the salt, poultry seasoning, and black pepper. Serve with turkey.
To toast the flour, spread it out on a rimmed cookie sheet. Place in 325°F oven and bake for 45 to 60 minutes. Gently stir every fifteen minutes until the flour is golden brown. It will seem a little smoky, but that’s just part of the process.