Place turkey breast in roasting pan along with onion and carrot.
Mix spices with olive oil. Rub turkey with olive oil.
Roast turkey at 400 °F for 15 minutes. Baste with margarine and chicken broth (optional).
Reduce turkey temperature to 350 °F and roast turkey, basting every 20 minutes with pan juices (or margarine and chicken broth), about 1 hour and 15 minutes, or until meat thermometer inserted in thick part of meat registers 165 °F.
Remove to carving board and let rest for 10 minutes.