With a sharp knife, make several incisions in the duck skin. Sprinkle with salt and press the peppercorns into the meat, making sure that they stick.
In a frying pan, heat the duck fat over low heat. Put in the duck breasts, skin-side down, and cook slowly for 10 minutes, until most of the fat runs out of the duck breasts and the skin is golden and crispy. Turn the duck over and cook fo