Combine vegetable stock, water, diced tomatoes, celery, carrots, onion, parsley, basil, oregano, rosemary, thyme, and bay leaves in a slow cooker.
Cook on low for 6-8 hours or on high for 3-4 hours.
During the last 30 minutes of cooking, add zucchini, pasta, and cannellini beans.
Remove bay leaves before serving.
Season with salt and pepper to taste.
Serve hot, garnished with grated Parmesan cheese.