Heat the butter in a 3- or 4-cup saucepan and when butter is melted add the flour. Stir with a wire whisk and when blended add the chicken stock gradually. When thickened and smooth stir in the cream and season with salt and pepper. Be careful in adding salt, however, because the chicken stock may have enough already.
Add the chicken pieces and heat thoroughly. If the sauce seems too thick, you may thin it by adding heavy cream, a little at a time, until the sauce is as thin as desired.
When ready to serve, place a slice of toast on each of four warm plates. Spoon the creamed chicken onto the toast and place a small sprig of parsley in the center of each serving. Serve immediately. As with the creamed ham, buttered peas and sliced tomatoes seasoned with salt and pepper go very well with this dish.