I absolutely love roast chicken. There is something so very comforting about roasting a chicken and even more so eating it.
Preheat oven to 425°F (220 °C)
Remove the chicken giblets and pat outside of the chicken. Add the carrots, potatoes, onion, and lemon to a large (4-quart) casserole dish. Season with 2 tablespoons olive oil, 1 teaspoon salt, and a generous amount of black pepper, stirring to evenly coat.
Put the chicken on top of the vegetables and liberally salt and pepper the inside of the chicken. Stuff the cavity with the bunch of rosemary/thyme, both lemon halves and the garlic half. Brush the outside of the chicken with the butter and sprinkle again with salt and pepper. Tie the legs together with kitchen string and tuck the wing tips under the body of the chicken.
If you have time, I highly recommend salting the chicken ahead of time (anywhere from 1-3 days), refrigerating it uncovered during this period.