I'm getting turkey anxiety. Been so long since I cooked a whole turkey, my vivid imagination is running wild. Every time I think about it I see my turkey either over cook or undercook. The bird will weight 15 pounds. It will be stuffed. I gather it will take between 3-3/4 to 4-1/2 to cook. It leaves a lot of room for error. Can there be some certainty in roasting turkey?