Heat the oil in a large saucepan. Add the garlic, cumin, garam masala and chilli powder. Cook over a low heat, stirring, for 1 minute. Combine the soup mix and water. Add to the pan with all the remaining ingredients, except the coriander or parsley. Bring to the boil, stirring, then simmer over a low heat for 20-25 minutes or until the lentils are tender. Stir occasionally. Stir in the coriander or parsley before serving.