In a large pot, heat the olive oil over medium heat.
Add the onion, carrots, and celery. Cook for 5-7 minutes, until softened.
Add the garlic and cook for 1 minute, until fragrant.
Pour in the diced tomatoes and broth. Bring to a simmer.
Add the cannellini beans and pasta. Cook for 10-12 minutes, until the pasta is tender.
Season with salt and pepper to taste.
Serve the pasta fagioli hot, topped with grated Parmesan cheese and chopped fresh parsley.
