Preheat the oven to 430°F (220°C). Prepare the roasting pan with a rack.

Remove neck and giblets from turkey. Pat turkey dry and place breast side up in the roasting pan.

Mix softened butter, olive oil, lemon juice, lemon zest, garlic, parsley, salt, and pepper until smooth. Reserve one-third.

Loosen skin on turkey breasts. Spread two-thirds of the butter mixture under the skin and rub remaining on exterior.

Sprinkle kosher salt and pepper generously on the skin for a seasoning crust.

Stuff the turkey cavity with onion, garlic cloves, and lemon pieces.

Tie the turkey legs together with kitchen twine for even cooking.

Roast uncovered for 20 minutes at 430°F until skin starts to brown. Baste with drippings and cover breast loosely with foil.

Lower oven temperature to 350°F (175°C) and roast approximately 13 minutes per pound until properly cooked.

Remove turkey from oven and rest for at least one hour before carving.