Preheat your oven to 425°F (220°C). Remove the chicken from the refrigerator about 30 minutes before cooking to bring it closer to room temperature. Pat the chicken completely dry inside and out with paper towels. Achieving a dry skin is the secret to getting that perfect golden-brown crunch.
Generously season the inside of the chicken cavity with salt and pepper. Stuff the cavity with the lemon halves, the halved head of garlic, the quartered onion, and half of the fresh herbs. This infuses the meat with incredible aroma and moisture from the inside out.
In a small bowl, mix the softened butter with the remaining chopped herbs, salt, and pepper. Gently loosen the skin over the breast meat and rub some of the herb butter underneath. Spread the remaining butter and olive oil all over the outside of the skin, ensuring every inch is coated.
Tie the legs together with kitchen twine and tuck the wing tips under the body. Place the chicken breast-side up in a roasting pan or a large oven-safe skillet. Roast for about 1 hour and 15 minutes, or until the thickest part of the thigh reaches an internal temperature of 165°F (74°C).
Once cooked, remove the chicken from the oven and transfer it to a cutting board. Tent loosely with aluminum foil and let it rest for at least 15 to 20 minutes. This allows the juices to redistribute throughout the meat, ensuring every bite is moist and flavorful before you carve.