Add the diced tomatoes, crushed tomatoes, carrots, potatoes, celery, onion, garlic, Italian seasoning, salt, pepper, bay leaves, vegetable broth, water, kidney beans, cannellini beans, and green beans to the slow cooker.
Cover and cook on low for 6–8 hours or on high for 3–4 hours, until the potatoes are tender.
Remove and discard the bay leaves.
Stir in the zucchini and ditalini pasta.
Cover and cook on high for an additional 10–15 minutes, until the pasta is tender.
Stir and serve warm.
Notes
*Refrigerate the leftovers in an airtight container for up to 5 days.