Slow Cooker Minestrone

Name: Slow Cooker Minestrone
Ingredients: 3 cups vegetable or chicken stock (preferably reduced sodium); 1 (28 ounce) can whole peeled tomatoes, chopped; 1 (15 ounce) can white kidney beans (cannellini), rinsed and drained; 2 carrots, peeled and chopped; 1 stalk celery, chopped; 1 cup onion, chopped; 1 teaspoon dried thyme; ½ teaspoon dried sage; 2 bay leaves; ½ teaspoonfreshly ground pepper; 2 cups cooked whole-wheat orzo (about 2/3 cup dry); 1 zucchini, sliced in quarters lengthwise, then chopped; 2 cups fresh spinach, stems removed and coarsely chopped; 4 tablespoon freshly grated Parmesan or Romano cheese; basil sprigs for garnish (optional)