In a large stock pot, heat oil over medium heat. Add celery, onion, carrot and garlic; stir occasionally for 5 minutes. Add stock, water, lentils, barley, and herbs. Cover and bring to a boil; reduce to simmer and cook for 45 minutes. Add can of tomatoes and simmer for another 15 minutes, stirring occasionally.
Notes
Adapted from ‘The New Good Life’ by John Robbins, 2010