How to Make It
Boil barley in a large pot of water until tender but still chewy (40 minutes). Drain.
Meanwhile, in large pot, heat oil over medium heat. Add zucchini and garlic; cook until zucchini begins to soften (2 minutes). Add tomatoes, broth, salt, and 1/2 cup basil; bring to a boil. Boil until the tomatoes have softened (7 minutes).
Divide the soup among 4 bowls. Add barley and remaining 1/4 cup basil; top with Parmesan, and serve.