Watercress, Carrot and Duck Gizzard Pork Shin Soup

Why people make this soup

I read in the paper that the US disease-control agency rated watercress the healthiest of all vegetables, giving it a full hundred — packed with folate, protein and many other nutrients. While it’s in season, it’s well worth putting watercress to work. I like blanching the tender leaves to fold into dumpling filling, and using the rest for a soup with carrot, sweet almond and pork shin — tasty, and traditionally valued for moistening the lungs and supporting the skin.