Preheat your oven to 400°F (200°C).
In a small bowl, combine the ghee with minced rosemary, thyme, sea salt, and black pepper to create an herb rub.
Pat the turkey breast dry with paper towels and rub the herb ghee mixture evenly over the skin and meat.
Peel and chop the carrots and parsnips into 1-inch chunks and place them at the bottom of a roasting pan.
Place the turkey breast on top of the vegetables and roast for 35-45 minutes, or until the internal temperature reaches 165°F.
Remove the turkey and vegetables from the pan and let the meat rest for 10 minutes on a cutting board.
Place the roasting pan on the stovetop over medium heat. Whisk the turkey stock and arrowroot powder together, then pour into the pan drippings.
Simmer the gravy for 2-3 minutes while scraping up the browned bits until thickened, then slice the turkey and serve with the vegetables and gravy.