Heat the oil in a heavy-based pan, then slowly cook the onions for around 10 mins until starting to caramelise. Stir in the garlic, ginger and spices and cook for a further 2 mins. Add the vegetables and canned tomatoes and bring to a simmer. Put the lid on and simmer for around 15 mins or until all the veg are tender. Stir in the chickpeas, heat through and serve with couscous or rice.