1. Preheat the oven to 220°C.
2. Halve the carrots lengthways, quarter the potatoes, lightly crush the unpeeled garlic cloves and pick the rosemary leaves then place them all in a large roasting tray.
3. Drizzle with oil, season with salt and black pepper, toss well and spread out in an even layer.
4. Rub the chicken all over with a pinch of salt and pepper and a drizzle of oil. Stuff the chicken cavity with the lemon and thyme, and then place it in the tray.
5. Reduce the oven temperature to 200°C, then add the chicken and roast for 45 minutes.
6. Remove the tray from the oven, use tongs to turn the vegetables over, and spoon any juices from the tray over the chicken. Return the tray to the oven for a further 30 minutes.
7. Pierce the chicken thigh with a knife, and the juices run clear, the chicken is done. Otherwise return the tray to the oven, cook for a little while longer and repeat the test.
8. Once cooked, transfer the chicken to a board, cover it with foil and leave it to rest for 10 minutes.
9. Using a sharp carving knife, carve up the chicken and serve with the roasted veg. Delicious with a green salad on the side.
