Turn the turkey so it is breast side down on the vegetables. Roast for 1 1/2 hours, then turn the turkey over to be breast side up. Sprinkle the reserved porcini seasoning over the turkey, then return it to the oven and roast for another 30 to 60 minutes, or until the thigh meat reaches 170 F and the breast reaches 160 F. If the turkey begins to brown more than desired, tent the top with foil.

When the turkey is cooked, transfer it to a serving platter. Cover it with foil and several bath towels to keep it warm.

Use a slotted spoon to remove and discard the vegetables from the roasting pan. Set the pan over medium-high heat on the stovetop. Once the juices in the pan begin to simmer, add the wine and scrape any browned bits up from the bottom of the pan. Add the shallots and cook until tender.

In a small bowl, whisk together the turkey stock and flour until smooth. While whisking continuously, add the flour-stock mixture to the roasting pan. Simmer for 5 minutes, stirring constantly. Remove from the heat and season with salt, pepper and a bit of truffle oil. Serve the gravy alongside the turkey.

Nutrition information per serving: 440 calories; 170 calories from fat (39 percent of total calories); 19 g fat (5 g saturated; 0 g trans fats); 185 mg cholesterol; 5 g carbohydrate; 1 g fiber; 1 g sugar; 58 g protein; 760 mg sodium.