If you are roasting turkey breast in the oven, then you have to be very careful that you do not overcook it. For bone-in turkey breast, the cooking time is roughly between 1 - 1 ¼ hour for a 2 to 3 pound bone-in turkey breast at 325 ºF. For a boneless turkey breast, the cooking time is slightly less, just under an hour for 2 - 3 pound turkey breast.