Dry fry the cumin & coriander seeds in a pan until you can smell them toasting, then crush them with the back of a spoon

Add in the tomatoes, harissa paste and 600mls water and bring to the boil

Add the sliced vegetables and the chickpeas, then stir in the turmeric and season well with salt & pepper

Transfer the mixture into a large tagine or casserole dish and cook covered for an hour or until the vegetables are tender

When the water has all been absorbed, stir in the lemon oil and fluff up the couscous with a fork

Serve the tagine over the couscous. It's a nice touch to garnish with fresh coriander leaves or to mix some through the couscous