Chop the onion, carrot, celery and garlic
in a food processor. Heat the oil over a
medium heat in a large saucepan. Add the
vegetables and potatoes, season well, then
reduce the heat and cover the pan. Gently
cook for about 5 mins until starting to soften,
then add the stock, turn up the heat and
bring to the boil. Simmer for 5 mins more,
or until all the vegetables are tender.
While the soup is cooking, grill or fry the
bacon until crisp, then cut into strips. Shred
the cabbage, discarding the core.
Whizz the soup in the food processor
until smooth, then return to the pan and
add the cabbage. Simmer for a few mins
until the cabbage is just tender, then season
to taste and serve scattered with the bacon.