In a small bowl, mix softened butter, oil, parsley and pepper.
Preheat oven to 500F adjusting the rack in the lower part of your oven.
Place turkey on the roasting pan.
Fold a square sheet of foil to form a triangle and rub with some oil from one side. Place that triangle over the turkey breast to shape it like the breast. Remove foil and set it aside keeping its shape.
Carefully, separate skin from the turkey breast using your fingers gently from front and back paying close attention not to tear the skin.
Stuff 3/4 butter mixture under the skin then massage the skin from above to spread the butter evenly.
Stuff cavity with the onion stuffing, tie turkey legs with kitchen twin. Tuck the wings too.
Rub the remaining butter on the outside.
Place turkey in oven and roast for 20-30 minutes.
Remove turkey from oven, reduce heat to 350F.
Cover the turkey with the foil that we've prepared earlier.
Return to oven and let it cook for another 2 hours or until a meat thermometer placed in between the breast and the thigh reads 165F.
Remove from oven and let it set for 30 minutes before carving.