3 carrots, peeled and finely diced
2 celery stalks, finely diced
2 leeks, trimmed, cut in half vertically and sliced into 2cm/戮in strips
400g/14oz baby potatoes, quartered
6 thyme sprigs, leaves picked
400g tin chopped tomatoes
150g/5陆oz dried red lentils
2 bay leaves
salt and freshly ground black pepper
1 tbsp olive or vegetable oil
1.25 litres/2录 pints vegetable stock
grated Italian-style hard cheese, to serve (optional)