1. Melt butter in a small saucepan over medium heat. When butter begins to bubble, whisk in flour. Cook, whisking often, until flour is cooked through and has a nutty fragrance, 10 to 15 minutes. Remove roux from heat and let cool to room temperature. Use roux immediately or transfer to an airtight container and keep refrigerated, up to 1 month.

2. Pour pan drippings into a fat separator to remove fat; set aside. Alternatively, pour pan drippings into a glass bowl and use a spoon to remove fat from top of drippings; set aside.

3. Place reserved roasting pan over 2 burners on medium heat. Pour wine into pan; using a wooden spoon, stir, scraping up bottom bits from pan. Let cook until wine is reduced to 3 tablespoons, about 2 minutes; add reserved pan drippings. Add 4 cups hot turkey stock and bring to a boil. Whisk in 4 to 5 tablespoons roux mixture and return to a boil; let simmer until gravy is thick, adding more roux if necessary. Season with salt and pepper.