Summer Vegetable Soup with Zucchini and White Beans

0 Pour the oil in a large saucepan or pot and place over medium heat.
1 Add the leeks, onion, fennel or celery, and carrot. Cook until the vegetables soften, about 5 minutes, stirring frequently so they don't brown.
2 Stir in the garlic and cook until fragrant, about 30 seconds. Add the cannellini beans, 6 cups water and 2 teaspoons salt. Bring to a simmer, then adjust the heat to low and continue to simmer for 15 minutes, with the pot partially covered.
3 Meanwhile, cook the pasta in a separate pot of salted boiling water until al dente. Drain and reserve.
4 Stir the zucchini into the pot and cook 1 or 2 minutes. Remove the pot from the heat. Stir in the cooked pasta and parsley.
5 Taste and season with more salt as need. Serve the soup garnished with chopped fresh fennel fronds (optional), a spoonful of pesto and the cheese.