In a large sauce pan, heat olive oil over medium heat and add onion, carrots and celery. Cook for 5 minutes until onion is translucent. Add the garlic cloves along with the dried spices, a large pinch of salt and stir to combine.
Add the chopped zucchini and squash and cook another 10 minutes until vegetables are tender.
Add the bay leaf, diced tomatoes and 6 cups vegetable broth and bring to a simmer.
Add the orzo and cook for roughly 10 minutes until orzo is cooked through and al dente. Since the orzo will continue to swell as the soup cooks, add more broth as needed.