Heat 3 tablespoons of the olive oil in a large saucepan over a medium heat, add the onions and garlic and sauté for 3 minutes. Add the peppers, aubergines and courgettes, mix well and cook for a further 5 minutes or until the vegetables have gained a little colour. Then add the tomatoes, water, herbs and seasoning, mix well and simmer gently over a reduced heat for a further hour, stirring from time to time. When cooked stir in another 6 tablespoons of olive oil and check the seasoning. Serve hot or at room temperature.