Heat large soup pot or Dutch oven over medium heat. Add 2 tablespoon olive oil. Add onions, celery, carrots and 1 teaspoon salt. Cook, stirring occasionally, for 8-10 minutes or until onions are soft and translucent.
2 tablespoons olive oil, 1 lg white or Spanish onion, diced, about 2 cups, 2 celery stalks, diced, about 1 cup, 2 med carrots, peeled and diced, about 1 cup, 1 teaspoon salt
Meanwhile, remove casings from sausages. When vegetables are soft add sausage and garlic. Using a wooden spoon, break up the sausage into small pieces and cook for 8-10 minutes or until sausage is cooked and starting to brown.
450 g (1 lb) Italian sausage, or your favorite kind, 8 cloves garlic, peeled and minced
Add chicken stock and Parmesan rind if using. Increase heat and bring to a boil. Reduce heat and simmer gently for 15 minutes.
6-8 cups chicken stock, homemade or store bought , Parmesan rind, optional, and/or freshly grated Parmesan cheese for garnish
Meanwhile, rinse and drain beans. Place ⅓ to ½ of the beans on a plate or cutting board and mash with a fork. After soup has simmered for 15 minutes add the whole and mashed beans and continue simmering for another 15 minutes.
2 (540 ml / 18 fl oz) cans white beans (such as kidney, navy, or cannellini)
Add arugula and chopped basil. Simmer 5 more minutes. Add more stock if you want to thin it out more. Remove from heat and add fresh lemon juice. Taste and adjust seasonings, adding more salt and/or pepper as needed.
2 cups arugula, packed. Add more to taste, ½ cup chopped fresh basil, 2 tablespoon lemon juice, fresh ground black pepper to taste
Garnish each serving with some freshly grated Parmesan cheese.