Instructions: Prepare the Crust: In a medium bowl, combine the chocolate cookie crumbs and melted butter. Mix until the crumbs are evenly coated with butter.
Prepare the Filling: In a medium saucepan, heat 1 cup of heavy cream and the marshmallows over medium-low heat, stirring constantly until the marshmallows are completely melted and the mixture is smooth.
Assemble the Pie: Remove the saucepan from heat and stir in the milk, crème de menthe, and crème de cacao. Add a few drops of green food coloring, if desired, to enhance the minty color. Let the mixture cool to room temperature.
Fold in Whipped Cream: Once the marshmallow mixture has cooled, gently fold in the whipped cream until fully incorporated.
Cool: Refrigerate the pie for at least 4 hours or until set. For best results, chill overnight.
Serving: Serve the blackberry pie warm or at room temperature, optionally with a scoop of vanilla ice cream or a dollop of whipped cream. Enjoy!