In a big pot, heat the oil and sauté (fry quickly) the onions and garlic.
Add the four cups of vegetable stock to the pot.
While the broth heats, dice the potato, kumara, celery and carrot and add to the pot.
Blend the tomatoes, dates and herbs then add to the pot.
Season to taste.
Cover the pot and simmer for 40 minutes to 1 hour.
Serve hot with some crispy bread.