Hearty Minestrone

Name: Hearty Minestrone
Ingredients: 2 teaspoons extra-virgin olive oil; 3 medium leeks, trimmed, washed (see Tip) and thinly sliced; 4 cups reduced-sodium chicken broth, or vegetable broth; 1 cup water; 1 large red potato, diced; 2 teaspoons dried thyme; ¼ teaspoon salt; ½ teaspoon freshly ground pepper; ½ cup whole-wheat orzo; 1 15-ounce can white beans, rinsed; 2 medium zucchini, quartered and thinly sliced; 1 pound fresh spinach, stems removed; 2 tablespoons cider vinegar; 2 tablespoons freshly grated Parmesan cheese, preferably Parmigiano-Reggiano