Roasted turkey or chicken wings are the base for this classic gravy.
Preheat the oven to 400°. On a rimmed baking sheet, toss the wing pieces, onion, celery, bay leaves, and oil; season with salt and pepper. Scatter 3 thyme sprigs, 1 sage sprig, and 1 rosemary sprig on top. Bake, rotating the baking sheet once during cooking, until the wings are cooked through, about 50 minutes.
Transfer the wings, onion, celery, and herbs to a large pot with a lid. Pour 1 cup water onto the baking sheet. Place the sheet on the stovetop over 2 burners; heat over high. Using a wooden spoon, scrape up any browned bits from the sheet. Pour the liquid into the pot. Add the stock, remaining herbs, and 3 cups water. Bring to a boil, skimming any foam that rises to the surface. Reduce heat to medium. Cover the pot, leaving the lid slightly ajar. Simmer, stirring occasionally, until the stock is very flavorful, about 2 hours. Using a fine-mesh sieve, strain the stock into a bowl. Discard the solids. You should have 4 1/2 to 5 cups of stock.
In a large pan, melt the butter over medium. Add the flour; cook, stirring often, until golden brown and smooth, 3 to 4 minutes. Slowly whisk in the stock. Simmer, whisking often, until the gravy thickens, about 5 minutes; season.
Up to 5 Days Ahead: Make the gravy; cover and refrigerate. Reheat the gravy before serving.
Thanksgiving recipes for planners and procrastinators here.