In a large saucepan over medium heat, cook the sausage until it's no longer pink. Drain the meat, remove it from the pan, and set it aside. In the same pan, saute the onion in canola oil until it's tender. Add the garlic and saute the aromatics for one minute longer.
Add the water, canned beans, tomatoes, broth, macaroni and pepper, and bring them to a boil. Cook the soup, uncovered, until the macaroni is tender, eight to ten minutes. Editor's Tip: Use additional chicken broth instead of water for even more flavor. If you think you'll have leftovers and don't want the pasta to absorb all the soup broth as it sits in the fridge, you may want to consider cooking the macaroni separately in a pot of boiling, salted water (though this will make for a thinner soup). When done, drain the pasta, add a scoop of pasta to each serving of soup, and store the noodles in a separate container.
Reduce the heat to low and stir in the sausage and spinach. Cook the soup until the spinach wilts, two to three minutes. Garnish the soup with cheese. Editor's Tip: This recipe calls for low-sodium broth and does not include added salt. To enhance the flavor, taste a sip of the soup before serving and add salt and something acidic, such as lemon juice or white wine vinegar, until the flavor sings.
