Preheat your oven to 400°F (200°C).

Remove the giblets from the cavity of the chicken. Pat the entire chicken completely dry with paper towels (inside and out). This is crucial for crispy skin!

In a small bowl, mash together the softened butter, minced garlic, chopped rosemary, thyme, salt, and pepper.

Using your fingers, gently separate the skin from the chicken breast. Rub half of the garlic herb butter under the skin directly onto the meat. Rub the remaining butter all over the outside of the chicken.

Stuff the cavity of the chicken with the lemon halves and a few wedges of onion. Tie the legs together with kitchen twine.

Place the remaining onion wedges, baby potatoes, and carrots into the bottom of a large cast-iron skillet or roasting pan. Drizzle with a little olive oil and salt.

Place the buttered chicken directly on top of the vegetables.

Roast uncovered for 1 hour and 15 minutes to 1 hour and 30 minutes, or until the juices run clear and a meat thermometer inserted into the thickest part of the thigh reads 165°F.

Remove from the oven and let the chicken rest for 15 minutes before carving to allow the juices to redistribute.