Heat the oil with the butter in the base of a tagine or a large, heavy-based saucepan over a medium heat, stir in the onion, ginger and cinnamon sticks and cook for 2–3 minutes to allow the flavours to mingle. Add the chicken thighs and stir to coat well, then cook for 1–2 minutes. Toss in the apricots.
Pour in enough water to cover the base of the tagine or saucepan, bring to the boil, then reduce the heat before covering and cooking gently for 15 minutes.
Beat the harissa, honey and chopped tomatoes together in a bowl, season with salt and pepper and tip the mixture into the tagine or saucepan. Re-cover and cook gently for a further 40 minutes to let the flavours mingle. Scatter the coriander over the top and serve with chunks of crusty bread and a salad, if liked.