Curried Carrot & Apple Soup

Serves:

• 1 tablespoon extra-virgin olive oil
• 1 large onion, chopped (2 cups)
• 1 stalk celery, finely chopped
• 1 tablespoon curry powder
• 5 large carrots, peeled and thinly sliced (3 cups)
• 2 large McIntosh or other apples, peeled and coarsely chopped (3 cups), peeled and coarsely chopped (3 cups)
• 1 bay leaf
• 4 1/2 cups reduced-sodium chicken broth
• 1/4 teaspoon salt
• Freshly ground pepper to taste
• 2 tablespoons low-fat plain yogurt for garnish (optional)
• 1 tablespoon chopped fresh parsley, dill or basil for garnish (optional)