In a medium bowl, mix together the softened butter, minced garlic, chopped rosemary, thyme, sage, lemon zest, salt, and pepper until well combined.
Pat the turkey dry with paper towels, both inside and out. Carefully loosen the skin from the turkey breast by sliding your fingers between the skin and the meat.
Place half of the garlic herb butter mixture under the skin, spreading it evenly over the breast meat. Rub the remaining butter all over the outside of the turkey.
Stuff the turkey cavity with quartered onion, halved lemon, and a few sprigs of extra herbs for added flavor.
Tie the turkey legs together with kitchen twine and tuck the wing tips under the bird to prevent burning.
Place the turkey on a rack in a roasting pan, breast side up. Surround the turkey with chopped carrots and celery. Pour the chicken broth into the bottom of the roasting pan.
Roast the turkey in the preheated oven, basting it every 30 minutes with the pan juices. Cook until the internal temperature reaches 165°F (74°C), approximately 3 to 3.5 hours.
Once done, remove the turkey from the oven and let it rest for at least 20 minutes before carving to allow the juices to redistribute.
Notes
Let the turkey rest before carving for better juice distribution.