Tip the couscous into a heatproof bowl. Stir the salt into the measurement water and pour over the couscous. Cover with a clean tea towel and leave to stand for about 10 minutes. Using your fingers, rub the oil into the grains for 4–5 minutes until light, airy and any lumps are broken up.
Heat the butter or ghee in a heavy-based frying pan, stir in the spices and fry for 2 minutes until they emit a nutty aroma. Toss in the pine nuts, apricots and harissa, then add the couscous, mix well and season.