Preheat the oven to fan assisted 190C / 200C / 400F/ gas 6.
Mix 1 tsp of harissa with the soft dried apricots and stuff the lamb shoulder.
Rub the remaining harissa on the lamb and season with salt and place in a baking tray.
Cook in the oven for 10 mins then reduce the temperature to fan assisted 140C / 160C / 325F / gas 3 and roast for 15 mins per 500g.
Test your lamb just before the 15 mins are up and roast a little further if the temperature readings are not as you desire (45C for rare, 60C for medium done and 70C for well done,
(45C for rare, 60C for medium done and 70C for well done).
Take the meat out and rest it for at least 15 mins before carving.