Step 1Trim any excess fat and sinew from the duck breast. Using a very sharp knife, lightly score the skin in a crosshatch pattern with lines spaced approximately one-fourth inch apart. Season with a pinch of salt.
Step 2Set up a work space as per the folded wrapping instructions at left. Carefully fold up the duck breast taking time to ensure that all the air is pushed out of the packet. Repeat and secure ends with tape. Cook for 35 minutes in a water bath at 140 degrees.
Step 3Remove from the water and allow the duck to rest for 5 minutes. Remove the breast from the plastic and dry the skin. In a non-stick pan heated over medium heat until hot, add a light film of oil and when the oil is hot but not smoking cook the breast skin-side down to render out some of the fat and crisp the skin. Rest briefly, then slice and serve.