Refreshing Kale and White Bean Soup with Lemon

I whipped up this soup quickly this afternoon and I'm quite pleased with the flavor. The lemon and herbes de provence are quite refreshing.

Ingredients (serves 6 or so):
Olive oil
6 cups water
3 veggie bullion cubes
1 medium onion
2 carrots
1 stalk celery
1 small zucchini
1 bunch kale 
2 cans (15.5 ounces each) cannellini beans (white beans)
1 lemon
herbes de provence
1 small ripe avocado for garnish

Instructions:

1. Dice the onion, carrots, and celery and saute in about 2 tablespoons olive oil in a large soup pot. Once these ingredients are softened, add 6 cups of water and the vegetable bullion (or just use six cups vegetable stock). Turn the heat down and let the stock simmer.

2. Strip the kale leaves from the stalks and discard the stalks. Rinse the kale well in a colander and rip the leaves into bite sized pieces. Add to the soup.

3. Rinse the beans and add to the soup.

4. Cut the zucchini into bit sized pieces (I typically cut them in half, then half again, and then chop them). Add to the soup.

5. Add herbes de provence to taste. I used about 3 teaspoons or so.

6. Zest a lemon into the soup and then squeeze half a lemons worth of juice in as well.

7. Simmer on medium heat until the kale is soft and the zucchini is cooked.

8. Serve with a few slices of avocado and a squirt of lemon.