Chicken Breasts in Vinegar

Preparation:

Preparation: Heat two thirds of the butter in a saucepan and place the chicken breasts in it after having lightly beaten them. Let them brown on both sides, salt and pepper them. Cover the pan and cook over low heat for 20 minutes. Meanwhile, in a small pan, flavor the chopped shallots with a knob of butter without letting them brown too much. Wet them with the vinegar and, when half of it has been consumed, remove from the heat, add the remaining butter, mix. Arrange the breasts in a warm serving dish and pour over the sauce. Serve them.