Wash the vegetables, peel the courgette, cut into 3 parts and empty it by using a balling spoon. Cut the top of the tomatoes and the peeled onions and empty the inside trying not to break the vegetables. Chop the obtained pulp. Place the whole onions in the Steam Case with 100 ml water, close and cook in the microwave for 4 minutes (oven at 200ºC, 6 minutes). Move away, pour the water on the couscous in a bowl and leave it hydrate. Mix vegetables with couscous, cumin, salt and pepper and stuff the vegetables. Pour 100 ml water in the case, place onto the tray and arrange the vegetables. Close and cook in the microwave for 5 minutes. (oven at 200ºC, 12 minutes) until vegetables are tender.