Carefully add the Marsala wine to the skillet and bring to a boil, scraping up any browned bits with a wooden spoon. Cook over moderate heat until reduced by half, about 5 minutes. Add the broth along with chicken breasts and any accumulated juices and cook until the chicken is white throughout and the pan juices have thickened, about 5 minutes. Swirl in the remaining 1 tablespoon of butter, then stir in the parsley, chives and reserved bacon. Serve.