Add them to a 6-qt or larger slow cooker. Then add the frozen mixed vegetables, diced tomatoes, garlic, and Italian seasoning. Pour in the vegetable broth and stir.
Place the lid on the slow cooker and cook on low for 8 hours or high for 6 hours.
Once cooked, stir and taste the soup and adjust the seasoning if needed.
Serve and enjoy!
Notes
To store the leftovers, let the soup cool, then transfer it to an airtight container. You can keep the soup in the refrigerator for up to 3 days.