Preheat the oven to 200°C (gas 6). Arrange all the vegetables in a large shallow roasting tin, leaving the garlic cloves whole but peeled. Drizzle over the olive oil and season well with black pepper.
Roast the vegetables for 45–50 minutes, turning them occasionally, until tender.
Meanwhile, put the couscous in a deep ovenproof dish, pour over 500ml boiling water, cover, and leave for 5 minutes to allow the grains to soak up the water. Cover tightly with foil and put in the oven with the vegetables for their final 15 minutes, to keep warm.
Fluff up the cooked couscous with a fork, stir in the butter and herbs and season to taste. Serve the roasted vegetables piled on top of the couscous. Sprinkle with harissa or chilli sauce, to taste.
Harissa is a fiery North African sauce made from a mix of red chillies, garlic, coriander, cumin, caraway, mint and olive oil. You'll find it in larger supermarkets or you can use any chilli sauce or spicy tomato sauce.
A creamy yoghurt raita, pepped up with diced green chillies and cooling cucumber would also make a good accompaniment.
I spread the vegetables out over two roasting pans to make sure they were not too crowded. If they're too crowded they steam instead of roast. Once they were done I stirred the Harissa right in to the roasted vegetables. They were even tastier reheated the second time around. The flavors really melded together. Make extra! - 06 Mar 2012