Combine 100g of yoghurt, 4 cloves garlic, ground cumin, cloves, paprika, juice of 1 lemon, cinnamon, star anise, bay leaves and the finely chopped stems of the coriander. Mix the diced lamb through and marinate for 3 hrs in the refrigerator. Transfer the lamb to a tagine or any lidded ceramic casserole dish, and braise in a 180°C oven for 1 & 1/2 hrs.
Prepare the couscous by soaking equal amounts of couscous and cold water in a bowl with a large pinch of salt and stand for 30 mins. Fluff the grains with a fork before serving. To make the spiced yoghurt dressing, toast the caraway, cumin and coriander seeds in a dry pan until fragrant. Combine these in a blender with the roasted capsicum, two garlic cloves, chillies, juice of half a lemon and 100g of yoghurt. Add salt and pepper to taste and chill.
To serve, spoon the couscous around the lamb in the tagine and allow it to soak up the juices. Garnish with chopped coriander leaves, lemon wedges and the spiced yoghurt dressing.