01 - Preheat the oven to 400°F for roasting.
02 - In a small bowl, whisk together olive oil, lemon juice, lemon zest, chopped basil, thyme, garlic, salt, and pepper until well combined.
03 - Pat the chicken completely dry with paper towels and place it in a roasting pan.
04 - Gently loosen the skin over the breasts and thighs with your fingers. Rub half of the marinade underneath the skin, then massage the remaining mixture over the exterior of the chicken.
05 - Fill the chicken cavity with lemon slices, thyme sprigs, basil leaves, and quartered onion.
06 - Secure the legs together with kitchen twine to ensure even cooking.
07 - Roast for 1 hour to 1 hour 10 minutes, until juices run clear and a meat thermometer inserted into the thickest part of the thigh registers 165°F.
08 - Allow the chicken to rest for 10 minutes before carving. Serve with the pan juices drizzled over the meat.