2 tablespoons extra-virgin olive oil 1 large onion, thinly sliced 2 leeks, white and tender green parts only, thinly sliced 2 garlic cloves, minced 1 cup pearled barley 8 cups low-sodium vegetable broth 4 cups water 1 1/2 pounds celery root, peeled and cut into 1/2-inch cubes 1 pound parsnips, peeled and cut into 1/2-inch pieces Salt [ ... ]