"This hearty yet healthy Italian classic features humble ingredients that make a big impact. Escarole is transformed by heat, from a bitter green into something soft, mellow, and sultry. If you can’t find escarole, substitute an equal amount of coarsely chopped lacinato kale, red kale, or Swiss chard. Parmesan cheese lends savory depth and body to the broth, while accents of pancetta add richness. As with most soups, the longer it sits, the better it gets, making this recipe a great make-ahead candidate. Bonus: One serving delivers more than a quarter of the day’s calcium and almost 30% of your daily potassium goal...."