Use chicken breasts or mackerel instead of the lamb or use 400g cooked rice , drained and rinsed instead of couscous.
Heat grill to medium. Tip the couscous, chickpeas and lemon zest into a large bowl and pour over the hot stock. Cover with cling film and leave to stand for 10 mins, until all the stock has been absorbed.
Smear 2 tsp harissa paste over the lamb chops, season to taste, then grill for 3-4 mins each side until crisp outside and medium rare in the middle. Cover, then rest for a few mins. Mix the remaining harissa into the yogurt, then season to taste.
Fold the rocket through the warm couscous, breaking up any clumps with a fork. Serve with the chops and a drizzle of harrissa and yogurt dressing.