You don't necessarily need a tagine dish to make this classic Moroccan chicken with green olives and preserved lemon. If you are short on time, let the chicken marinate for 1 hour or more, but ideally give it a full day to marinate.
If using a tagine dish, place the chicken in the dish 15 minutes before the end of cooking. Pour a generous ladle full of sauce over it and sprinkle with the preserved lemon and olives. Cover and place in the oven at moderate heat (180 C / Gas 4) for 15 minutes.