1. Remove and discard giblets and neck from turkey. Trim excess fat. Starting at neck cavity, loosen skin from breast and drumsticks by inserting fingers, gently pushing between skin and meat. Mince 3 garlic cloves; combine minced garlic, chopped rosemary, and next 4 ingredients (through pepper) in a small bowl. Rub butter mixture under loosened skin and rub over breast and drumsticks. Lift wing tips up and over back; tuck under turkey. Place remaining 6 garlic cloves and rosemary sprigs in body cavity. Tie legs together with kitchen string. Let turkey stand 1 hour at room temperature.
2. Preheat oven to 500°.
3. Place turkey, breast side up, on the rack of a roasting pan coated with cooking spray. Place rack in pan. Bake at 500° for 30 minutes. Reduce heat to 250°; bake for 2 hours or until a thermometer inserted into meaty part of thigh registers 165°. Remove from oven; cover loosely with foil. Let stand 20 minutes. Discard skin.