In a large pot, over medium heat, bring the tomatoes and their liquid to a simmer. Cook for 2 minutes. Add the broth, white beans, and kidney beans (if using) and bring to a simmer. Add the green beans and cook until tender, about 3 minutes. Add the salt, pepper, and spinach and stir until wilted. Ladle into bowls and sprinkle with the Parmesan. Serve with the bread.