01 - Preheat oven to 425°F (220°C). Position rack in a large roasting pan.
02 - Pat chicken dry with paper towels. Season cavity with 1 teaspoon salt and 1/4 teaspoon pepper.
03 - In a small bowl, thoroughly blend softened butter, olive oil, minced garlic, chopped rosemary, thyme, parsley, lemon zest, lemon juice, and remaining salt and pepper.
04 - Gently loosen skin over breasts with fingers. Spread half the herb butter beneath skin; remainder over entire exterior of chicken.
05 - Fill cavity with quartered lemon, halved garlic head, and onion quarters.
06 - Scatter carrot and celery chunks in bottom of roasting pan. Place chicken breast side up on rack or directly atop vegetables.
07 - Pour wine or broth into pan, ensuring it does not make contact with chicken skin.
08 - Roast chicken for 20 minutes at 425°F (220°C).
09 - Lower oven temperature to 350°F (180°C). Continue roasting for 1 hour, until juices run clear and internal thigh temperature reaches 165°F (75°C).
10 - Baste chicken halfway through roasting with pan juices for enhanced flavor and moisture.
11 - Rest chicken, lightly tented with foil, for 10–15 minutes prior to carving. Present with roasted vegetables and pan juices.