In a pot, soften the onion in some oil over medium heat. After 2 minutes add the garlic and celery, stir and cook for another minute. Pour the water, broth, tomatoes, dry spices + chili flakes, and your mixed vegetables in, stir and bring to a gentle simmer for 12-13 minutes. If you are adding softer veggies like zucchini that cook really fast I recommend adding them with the baby spinach about 5 minutes in so they don’t get all mushy.