In a large bowl, combine the couscous, raisins, salt, coriander, cinnamon, and cayenne. Pour the boiling water over the mixture, cover, and let stand until the water is absorbed and the couscous is puffed, about 6 minutes.
Uncover and fluff with a fork. Add the pistachios, mint, oil, and orange juice. Adjust seasoning, to taste. Serve hot.
Yield: 4 servings