Prepare: Preheat stove to 120 °C, plate and plate.
Filling: Stir mustard, tangerine juice, salt and cayenne pepper, mix with the remaining ingredients, stand briefly.
Meat: Score the fat layer of the duck breasts crosswise. Fill the duck breasts, close with toothpicks. Fry first with the fat layer facing downwards, then on the other side in an empty heated pan (chrome steel or cast iron) for approx. 5 minutes each, the fat layer must be crispy. Season bottom side, place on preheated plate with fat layer facing up. Cook in the heated stove for approx. 40 min. The meat can be kept warm at 60 degrees for about half an hour.
Tangerine sauce: bring sugar and water to a boil in a chrome steel pan without stirring. Reduce temperature, simmer over low heat while occasionally moving the skillet back and forth, until a light caramel forms, pull skillet off the heat. Add white wine, tangerine juice and chicken stock, make half. Mix cornstarch with a little water, add while stirring, make about 1 minute. Add grated tangerine peel, season.
To serve: 20 min before serving, warm tangerine slices in the stove. Cut meat diagonally into tranches, arrange on plates with a little sauce and the warm tangerine slices.
Serve with: Dry rice
Matching wine: With this dish you can make interesting experiments: The fruity-sweet filling