Trim any fat off the lamb and cut it into 2.5 cm (1 in) cubes. Put the meat, onions, garlic, cayenne pepper, cinnamon, ginger, paprika and saffron into the bottom of a double boiler or a large saucepan, season to taste and add enough water to cover. Bring the contents to the boil, then cover the pan, reduce the heat to low and simmer for 1 hour 30 minutes.
Add the apricots, carrots, turai, tomatoes, coriander and parsley to the pan and cook, covered, for a further 15 minutes.
Meanwhile, put the couscous into a bowl, add just enough cold water to cover it and leave it for 5 minutes to absorb the liquid.
Transfer the couscous to the top of the double boiler, or, if using a saucepan, put it into a sieve, and steam the couscous over the stew for 15 minutes until warm, fluffed up and tender. Add salt to taste.
To serve, spoon the couscous onto a serving dish; lift the lamb and vegetables from the pan with a slotted spoon and lay them on top of the couscous and sprinkle them with chopped coriander and parsley. Pour the broth into a jug or bowl to serve separately and let people help themselves at the table.