Preheat oven to 325°F (165°C).

In a bowl, mix together butter, rosemary, thyme, garlic, salt, and pepper.

Clean the turkey and remove any giblets. Pat dry with paper towels.

Rub the butter mixture all over the turkey, both under and over the skin.

Stuff the turkey cavity with onion, carrots, and celery.

Place the turkey on a roasting rack inside a roasting pan.

Pour chicken broth into the bottom of the roasting pan.

Roast the turkey in the preheated oven for about 3-4 hours, or until the internal temperature reaches 165°F (74°C). Baste the turkey occasionally with the pan juices.

Once cooked, remove from the oven and let rest for 20 minutes before carving.