Braised Duck with Green Olives

Cut the duck into fairly large pieces, dry these off well with a clean cloth, and put them into the marinade. Leave the bowl in a cool place for 48 hours turning the pieces from time to time. Fry the butter and oil gently in a pan, and then put in the pieces of duck, well-drained, dried with a spotlessly clean cloth and seasoned with more salt and pepper. Brown the pieces over high heat, pour in the brandy and allow to evaporate, reduce, add the liquid from the marinade, puree through a colander, reduce by half, lower the heat and then add the flour, a little at a time and stirring constantly. After some minutes, add the tomato sauce and the stock. Continue cooking over moderate heat, stirring well, for about half an hour. When the cooking is finished, remove the pieces of duck with a fork, drain them, and transfer to a bowl. Finely sieve the cooking liquid. Put the duck and liquid back into the pan, mix in the olives, previously blanched and well dried, and leave to gain flavor for some minutes over moderate heat. Arrange the duck and the olives covered in sauce on a very hot serving plate.