Heat the oil in a large cooking pot and fry the bacon in it until the fat begins to run.
Then stir in the prepared carrots, onion and celery and, with the heat fairly high, toss them around to brown them a little at the edges. Now stir in the washed, drained lentils plus the contents of the tin of tomatoes followed by the crushed garlic then the stock.
As soon as the soup comes to the boil, put a lid on and simmer, as gently as possible, for about 1 hour. About 15 minutes before the end add the cabbage. Taste and season. Just before serving stir in the chopped parsley.