1) Bake the pastry as directed and let it cool.
2) Combine together the marshmallows and milk in top of a double boiler.
3) Place the mixture over hot water and stir well till the marshmallows melt.
4) Add the broken chocolate bar and continue to stir till the chocolate has melted and the mixture is smooth.
5) Cool the mixture to room temperature.
6) Whip the cream and fold it into the cooled chocolate-marshmallow mixture.
7) Turn the concoction into the baked pastry shell.
8) Use waxed paper or clear plastic wrap to cover the filling.
9) Refrigerate for a minimum of 6 hours, or overnight, till set.
10) Remove the wrap and put the chilled pie on a serving platter. Cut into wedges and serve chilled or at room temperature. Makes an excellent dessert.