You don't need the duck meat, so save that for another recipe.
Put the fatty skins in the freezer and leave until frozen. Finely slice.
Heat the duck fat in a pan to 190C, or until a cube of bread turns golden in 30 seconds.
Add the shreds of duck skin and fry until golden and crisp. Drain on kitchen roll, and leave to cool so they crisp up.
Recipe courtesy of Matt Tebbutt.