Winter Provencal Vegetable Soup

Heat in a large soup pot over medium-low heat:
- 2 Tbsp olive oil
- 1 medium chopped onion
- 1 small leek, chopped
- 1 medium parsnip, chopped
- 1 large celery stalk, chopped

Stir in:
- 2 medium ripe tomatoes (peeled, seeded and chopped)
- 1 small potato, peeled and chopped
- 8 cups water
- 2 tsp salt
- a pinch of saffron

Bring ingredients to a boil, reduce heat, and simmer until the potatoes are tender (about 30 minutes). Stir in:
- 1 15-1/2 or 19 oz can Great Northern white beans, rinsed and drained
- 1 small zucchini, quartered lengthwise and sliced
- 4 oz green beans, cut into 1-inch pieces

Simmer for about 10 minutes.

For the pistou, puree in a blender:
- 2 cups fresh basil leaves
- 2 cloves garlic, chopped
- 1/4 cup extra-virgin olive oil

Remove soup from heat and immediately stir in the pistou along with:
- 2/3 cup coarsely grated Parmesan cheese
- 1 tsp ground black pepper

Serve hot in warm soup bowls or cold in room-temperature soup bowls.