01 - Set the oven temperature to 375°F.
02 - Combine olive oil, rosemary, thyme, sage, garlic, salt, and pepper in a small bowl until well mixed.
03 - Dry turkey legs thoroughly with paper towels. Evenly coat them with the prepared marinade.
04 - If using, spread onion, carrot, and celery chunks across the base of a large roasting pan to form a vegetable bed.
05 - Set the turkey legs atop the vegetable bed or directly into the roasting pan if not using vegetables.
06 - Cook uncovered for 1 hour and 15 minutes, occasionally basting with pan juices, until skin is golden and internal temperature reaches 170°F.
07 - Allow the turkey legs to rest for 10 minutes prior to serving to retain juices.