Heat a deep frying pan. Add oil, cumin, ginger, saffron and onions and cook 1 minute. Add the pumpkin, sweet potatoes, carrots, stock and honey. Cover and simmer 25 minutes or until vegetables are soft.
Place couscous in a bowl and pour over the boiling water. cover and let stand 5 minutes until all the liquid is absorbed. Fluff up with a fork, then stir through the coriander and cashews.
Serve the tagine and couscous together with some of the broth spooned over.