01 - Preheat the oven to 425°F.
02 - Pat the chicken dry with paper towels and rub olive oil evenly over the skin.
03 - Season the chicken inside and out with kosher salt and black pepper.
04 - Fill the cavity with halved garlic head, lemon quarters, thyme, and rosemary sprigs.
05 - Tie the legs together securely using kitchen twine and position the bird breast-side up in a large roasting pan.
06 - Spread softened butter over the chicken breast and thighs to encourage a crispy skin.
07 - If desired, arrange the prepared carrots, onions, and celery around the chicken in the pan.
08 - Roast for 1 hour and 15 minutes or until the internal temperature reaches 165°F at the thickest part of the thigh and the juices run clear.
09 - Allow the chicken to rest for 10 minutes before carving. Serve with roasted vegetables and pan juices.