Combine ingredients for marinade in bowl with tight-fitting lid. Place duck breasts in marinade, cover, and refrigerate for 24 hours, turning occasionally.
Combine pistachios, panko, flour, and a dash of salt and pepper in shallow dish.
Remove duck breasts from marinade. Press into nut mixture. Refrigerate for at least two hours just before cooking.
When ready to serve, preheat oven to 325°F. Using half duck fat and half canola oil, put enough into a large, heavy-bottomed, nonstick frying pan to just cover the bottom of the pan.
Heat fat over medium-high heat until hot but not smoking. Carefully place duck breasts in pan, reduce heat to medium, and sear breasts on both sides to a golden brown, approximately one minute. Remove from pan, place on a baking sheet, and roast in oven for five to seven minutes until medium rare.
Let rest five minutes. Slice with very sharp knife so crust does not fall apart. Serve with cassis-currant glaze.
Combine ingredients in a nonreactive, heavy-bottomed saucepan. Bring to boil, reduce heat until sauce maintains a slow simmer, and slowly reduce until thickened.