Classic Turkey Gravy

Name: Classic Turkey Gravy
Prep time: 30 min
Cook time: 2 h 30 min
Total time: 3 h
Cuisine: American
Ingredients: 2 tablespoons unsalted butter; 1 medium onion or leek, or 2 shallots, sliced; Neck and giblets from your turkey (discard the liver); 8 cups low-sodium chicken broth; 3 sprigs thyme, parsley, rosemary and/or sage; 1 bay leaf; Turkey drippings from your roasting pan; 1/2 cup all-purpose flour; Dash of Worcestershire sauce; Kosher salt and freshly ground pepper; 2 tablespoons cold Flavored Butter, recipe follows (optional)