Melt butter and olive oil in a dutch oven or large stock pot over medium-high heat. Add the onions, carrots, celery, garlic, and zucchini. Let cook for 8 to 10 minutes or until tender, stirring occasionally. Add the diced tomatoes, beans, tomato sauce, broth, basil, parsley, oregano, and freshly ground pepper. Stir together and let come to a low boil. Once boiling, turn down the heat to medium and let simmer 15 to 20 minutes. Add the spinach and pasta, and let cook until the pasta is done. Serve with a sprinkling of parmesan cheese.