Heat oil in a soup pot over medium heat. Add carrots, celery and onion and cook until onion is translucent, about 5 minutes. Add garlic and thyme. Season with salt and pepper; cook until fragrant, another 3 minutes. Add beans, tomatoes, broth and parsley. Bring to a boil. Reduce heat and simmer until vegetables are tender, about 30 minutes. Season to taste with salt and pepper. Serve with parmesan cheese on top.