01 - Preheat your oven to 425°F for optimal roasting temperature.
02 - Combine the minced garlic, lemon zest, lemon juice, olive oil, salt, pepper, thyme, and rosemary in a small bowl. Mix thoroughly to create a uniform marinade.
03 - Pat the chicken completely dry with paper towels. Gently lift the skin over the breast area and rub half of the marinade directly onto the meat beneath the skin for maximum flavor penetration.
04 - Rub the remaining marinade evenly over the entire exterior surface of the chicken, ensuring complete coverage.
05 - Fill the chicken cavity with the lemon slices and additional fresh herb sprigs if desired to infuse interior flavors.
06 - Place the quartered onions, carrot chunks, and celery pieces in the bottom of a large roasting pan to create a vegetable bed.
07 - Set the chicken on top of the vegetable bed, breast side facing up for even cooking and browning.
08 - Roast for 1 hour 15 minutes until the juices run clear when the thigh is pierced and a meat thermometer inserted into the thickest part of the thigh registers 165°F.
09 - Allow the chicken to rest for 10 to 15 minutes before carving to redistribute juices and ensure moist meat. Serve with the roasted vegetables and pan juices.