Start by crushing your chocolate cookies into fine crumbs using a food processor or a rolling pin in a zip-top bag. In a mixing bowl, combine the cookie crumbs with melted butter until it resembles wet sand. Press the mixture firmly into the bottom of a 9-inch pie dish to form an even layer. Chill the crust in the refrigerator for about 30 minutes to set and become firm.

In a large mixing bowl, pour in the cold heavy cream and whip it with an electric mixer on medium-high speed until stiff peaks form, which should take about 3-5 minutes. In another bowl, blend softened cream cheese, powdered sugar, peppermint extract, and green food coloring until smooth and creamy.

Gently fold the whipped cream into the cream cheese mixture using a spatula. Start by adding a third of the whipped cream to lighten the cream cheese mixture, then carefully fold in the remaining whipped cream until fully incorporated.

Pour the creamy mousse filling over the chilled chocolate cookie crust, using a spatula to smooth the top for an even surface. Cover the pie with plastic wrap and refrigerate it for at least 4 hours to allow it to set properly.

Once the Grasshopper Pie is fully set, remove it from the refrigerator and slice it into generous portions. For an added touch, top each slice with a dollop of whipped cream and a sprinkle of shaved chocolate, if desired.