Potato and Leek Sous Vide Soup

The slow, low, evenly distributed heat of cooking sous vide is an incredible way to develop a complex soup. In this soup, the long, slow extraction allows for the leek flavor to open fully, aided by the warm fat of olive oil—an excellent oil for a low-heat cook. The cashew-based cream sauce gives this country classic the feel of a chowder, but any of the other cream sauces in the book can be substituted if you have them on hand.