In a large Dutch oven, heat oil on medium heat; add onion and celery and sauté until translucent. Lower heat slightly and add spices; sauté for another minute.
Add broth, water, lentils, rinsed garbanzo beans, and simmer for 20 minutes.
Add orzo pasta and crushed tomatoes. Simmer for an additional 5-7 minutes, adding additional spices/salt/pepper as necessary.
Serve hot with crusty sourdough bread and season with additional salt as needed.