15-Minute Lentil Soup

INGREDIENTS

• 1 teaspoon extra-virgin olive oil
• 1/2 small onion, finely chopped
• 1 carrot, finely chopped
• 1 celery stalk, finely chopped
• 1 garlic clove, minced
• Coarse salt and ground pepper
• 14.5 ounces low-sodium vegetable or chicken broth
• 3/4 cup cooked lentils (from a 15-ounce can), rinsed and drained
• 2 teaspoons red-wine vinegar