In a large soup pot, bring vegetable broth, water, and barley to a boil. Reduce heat, cover and simmer for 20 minutes or until barley is tender.

Meanwhile, heat oil and 1 tablespoon water in a pan. Add onions, celery, carrots, garlic, tomatoes, beans, and red pepper flakes. Cover and simmer over low heat for 15 minutes or until vegetables are tender.

Add vegetable/bean mixture to barley pot, stir in spinach and pepper and simmer an additional 5 minutes or until spinach is wilted.