In a four-quart heavy pot, heat the olive oil over medium heat.

Add the onions and 1/4 teaspoon kosher salt. Saute the onions for eight to 10 minutes, stirring often. Cook until the onions have begun to brown and turn translucent.

Add the fennel and saute for two minutes, stirring often.

Add the celery and zucchini and stir. Cook for three to five minutes until zucchini begins to turn golden.

Add the carrots and the garlic and stir. Cook for about 40 seconds or until the garlic becomes very fragrant.

Add the tomato paste and stir until vegetables are coated.

Add the beans, crushed tomatoes, Italian seasoning, pinch of chili flakes, dried thyme, dried oregano, rounded 1/4 teaspoon kosher salt, vegetable stock and stir well.

Bring soup to a boil, lower to simmer, cover, and cook for 40 minutes.

Add the kale. Add the heel of the cheese and let it simmer in the soup for 10–15 minutes, then carefully remove it and set it aside.

Add dried pasta (if desired) and let it simmer in the soup until pasta is al dente.

To serve, ladle the soup into bowls and pile high with Parmesan or pecorino romano cheese and enjoy!