Sauté Vegetables:
Heat the olive oil in a large pot or Dutch oven over medium heat. Add the diced onion, carrots, and celery. Sauté for about 5-7 minutes, or until the vegetables are softened and the onion is translucent. Add the minced garlic and cook for another 1 minute, stirring occasionally.
Add Tomatoes and Broth:
Stir in the diced tomatoes (with their juices), white beans, kidney beans, chicken broth, oregano, basil, salt, and pepper. Bring the mixture to a simmer and cook for 10 minutes to allow the flavors to meld.
Cook the Pasta:
Add the pasta to the pot and cook according to the package instructions until al dente (usually around 8-10 minutes). Stir occasionally to prevent the pasta from sticking.
Add Greens (Optional):
If using spinach or kale, stir it into the soup during the last 2-3 minutes of cooking, allowing it to wilt and soften.
Serve:
Ladle the Pasta Fagioli into bowls. Top with a sprinkle of grated Parmesan cheese and fresh parsley if desired. Serve with crusty bread for dipping.