Preheat sous vide machine to 145ºF. Form a paste by mixing together the garlic salt, pepper, rosemary, thyme, and ghee in a small bowl.
Season the outside of the frozen turkey breast by smearing it with half of the paste. Add seasoned turkey breast to a vacuum-seal bag. Add lemon slices and vacuum-seal. Sous vide frozen turkey breast for 4 hours (3 hours for turkey + 1 hour to defrost).
When sous vide frozen turkey is done in the sous vide bath, Remove it from the hot water and shock the bag in an ice bath for 10 minutes. Remove turkey from the bag and pat dry.
Preheat broiler to high. Coat the turkey with the remaining seasoning paste. Broil turkey on high for 3 to 8 minutes, until golden brown. Rest at least 15 minutes before serving.
For planning purposes, prepare 1-2 pounds of turkey per person.