Roasted Turkey:

1. Let turkey sit at room temperature about 30-60 minutes prior to cooking. After it comes to room temperature, preheat oven to 325F and place rack at the lowest level in the oven. May have to remove top rack also.
2. Unwrap the turkey from its packaging and remove neck and giblets (tip: you can put them in the bottom of the roasting pan for flavorful gravy.) Drain all the juices and pat dry with paper towels. Place turkey breast side up on a rack in a roasting pan.
3. Season the inside of the cavity with a generous sprinkle of salt and pepper. Place the quartered onion, lemon, orange, garlic and sprigs of rosemary into the cavity, loosely but don’t over stuff. Tie the legs and tail of the turkey together with kitchen twine. Also, tuck wing tips under the body of the turkey.
4. Combine the butter/oil, herbs de provence, salt and pepper in a bowl. Use a pastry brush or your hands to coat the entire turkey with the herb butter. Gently separate the skin from the breast and rub herb butter under the skin of the breast.
5. Place pan on the lowest rack in the preheated oven and bake for 2 3/4–4 hours, or until thermometer reads 180° F in the thigh and juices run clear. You can cover breast and drumsticks loosely with foil towards the end of roasted to keep from overcooking.
6. Transfer Turkey to a large platter and let rest 20-30 minutes before carving.

To Make The Gravy:

1. Combine the drippings and cornstarch together in a small sauce pan. Place over medium heat and slowly whisk in a splash of milk. Stir in chicken broth a little at a time, adding more as the sauce thickens. Stop adding broth when you get to your desired consistency. Season with salt and pepper, if needed.