Remove any packet of giblets or gizzards and discard
Place turkey into a roasting pan.
Cut onion into fours and stuff pieces inside the cavity of the turkey
Stuff head of garlic into turkey cavity
Smear entire stick of room temperature butter all over the turkey.
Liberally sprinkle salt and pepper over the butter (I usually use 1-2 teaspoons salt and 1/2 teaspoon freshly ground pepper).
Place carrots and celery around the side of the turkey, in the pan.
Bake for 45 minutes at 400. Leave turkey in oven and baste it (use a turkey baster and use the baster to suck up the butter and juices and baste juices onto the top and sides and all around the turkey).
Bring oven temperature down to 350 and baste turkey every 30 minutes, cooking until internal temperature is 165 degrees. (approximately six minutes per pound of meat)
Notes
The nutrition information presented on this site should be considered an estimate as the calculations will change based on the exact products you use in your own kitchen.