Line unpricked pastry shell with a double thickness of heavy-duty foil. Bake at 450F for 8 minutes. Remove foil; bake five minutes longer. Cool on a wire rack.

Meanwhile, in a heavy saucepan, combine the marshmallow creme, chocolate chips, butter, unsweetened chocolate and coffee; cook and stir over low heat until the chocolate is melted and the mixture is smooth. Cool. Fold in the whipped cream; pour into the crust.

For topping, in a large mixing bowl, beat cream until it begins to thicken. Add confectioner's sugar; beat until stiff peaks form. Spread over filling. Refrigerate for at least 3 hours before serving. Garnish with chocolate curls if desired.