How to Make It
In a food processor or blender, puree the tomatoes with their juice. Set aside.
In a large pot, heat the oil over moderately low heat. Add the onion and cook, stirring occasionally, until soft, about 10 minutes. Stir in the garlic.
Add the pureed tomatoes, the sage, broth, water, and salt to the pot. Bring to a boil. Stir in the pasta and chickpeas. Bring the soup back to a boil, then reduce the heat. Cook, partially covered, stirring occasionally, until the pasta is tender, about 15 minutes. Stir in the parsley, pepper, and the 1/3 cup grated Parmesan. Serve topped with additional Parmesan.
Test Kitchen Tip Look for high-quality canned tomatoes for this soup, such as plum tomatoes from the San Marzano region of Italy.