Heat oven to 200C/180C fan/gas 6. Put the chicken into a plastic food bag with 2 tbsp of the harissa paste, all the ground coriander, 1 tbsp oil, a squeeze of lime and a grinding of black pepper. Marinate for 30 mins (up to 24 hrs). Tip into a roasting tin, drizzle with a little more oil, then roast for 1 hr until the chicken is dark golden and crisping on the top.
Lift the chicken out of the tin and onto a big plate. Turn the oven to low and keep the chicken warm, uncovered. Place the tin on the hob, spoon off excess fat, then add most of the chilli and fry for 2 mins until fragrant. Stir in the sugar, tomato purée and remaining harissa paste, then add the stock and bubble down for about 5 mins until you have a sticky sauce.
Season with salt and pepper and another squeeze of lime juice. (The chicken will keep in a low oven, uncovered, for up to half an hour. You can also decant the sauce into a saucepan and reheat it.) To serve, spoon the sauce over and around the chicken and scatter with the remaining chilli. Serve with the rice salad, salsa and wedges (see below).
For the rice salad, rinse the rice in a sieve until the water runs clear, then boil for 15 mins until just tender. Drain in a sieve, rinse under cold water to cool quickly, then drain well and tip into a big serving bowl. Whisk together the chives, golden syrup, cumin, vinegar and oil to make the dressing, season, then toss through the salad. If making ahead, keep chilled. Just before serving, chop the coriander and fold it in.