Heat olive oil in a large pot over medium heat. Add onion, garlic, carrots, and celery. Cook until vegetables are softened, about 5 minutes.
Add kale and cook until wilted, about 3 minutes.
Add white beans, broth, diced tomatoes, rosemary, and thyme. Bring to a boil, then reduce heat and simmer for 20 minutes.
Season with salt and pepper to taste.
Serve hot, topped with grated Parmesan cheese if desired.