01 - Set oven to 400°F and allow it to reach temperature before cooking.
02 - Combine olive oil, garlic, rosemary, thyme, smoked paprika, onion powder, salt, black pepper, and lemon juice in a small bowl to form the marinade.
03 - Pat turkey legs dry using paper towels. Apply marinade evenly over all sides of the turkey legs.
04 - Place sliced onion, carrots, and celery in the bottom of a large roasting pan to create a flavorful base.
05 - Set turkey legs atop the vegetable bed or directly on the roasting pan if skipping vegetables.
06 - Cook in the preheated oven for 1 hour and 20 minutes, turning once halfway through until skin is golden brown and internal temperature reaches 170°F.
07 - Remove from oven, tent with foil loosely, and let rest for 10 minutes prior to serving.