This is soup at its most basic — a great way to use up any vegetables malingering in your fridge. But beware that some vegetables tend to have a colonizing effect on a pot of soup: Squash makes it squashy, broccoli makes it broccoli-y, and dried herbs and tomato make it taste like diner minestrone, not in a good way. If you've got plenty of time, simply dump the barley in with the rest of the ingredients and add a half hour to the overall cooking time. But I'm usually rushing, so I use the two-pot method.
Yields 10 cups
Place barley and broth in a small pot and bring to a boil over low heat. Stir, lower heat to a simmer, cover, and let barley cook while you prepare the other ingredients, about 30 minutes.
Heat olive oil in a wide soup pot and sauté onion with 1 teaspoon salt over medium-high heat until translucent, about 5 minutes. Add garlic and the rest of the fresh vegetables, and allow this mixture to cook, stirring occasionally, for another 10 minutes or so.
Pour barley into the pot with its broth, and add another teaspoon of salt and 2 cups of water. Simmer covered until all the vegetables and barley are tender, about 45 minutes.
Add canned beans and another cup of water to keep the consistency soupy. Simmer 15 more minutes. Taste for salt, then serve garnished with a spoonful of olive oil and a sprinkle of parmesan.