Put the couscous in a bowl with the raisins, prunes and orange zest, then stir to mix thoroughly.
Pour the milk into a saucepan and bring just to the boil. Pour the hot milk over the couscous mixture, stirring well, then cover with foil. Leave to soak for about 10 minutes or until the grains of couscous are plumped up and all the milk has been absorbed.
Spoon the couscous into bowls and top with sliced nectarines and fromage frais. Serve immediately.