Preheat the oven to 200°C/fan 180°C/gas 6. Put all the vegetables in a large roasting tin. Add the lemon, garlic and thyme, then toss with oil and seasoning. Season the chicken and place on top of the vegetables, then roast for 50-60 minutes until the chicken is cooked (the juices will run clear when you pierce the thick part of the thigh with a skewer).
02.Remove the chicken to a board and return the veg to the oven to crisp up. Leave the chicken to rest somewhere warm under foil for 15-20 minutes, then carve enough meat for 4-6. Serve the chicken with the roasted vegetables and any cooking juices.