Make the Crust: Preheat oven to 350 degrees F. Combine the Oreo cookie crumbs and the melted butter in a medium bowl and toss with a fork until the crumbs are evenly moistened. Transfer the crumbs to a 9-inch pie plate. Press the crumbs evenly into the bottom and up the sides of the pan, forming a crust. Refrigerate the lined pie plate for 20 minutes. Bake for 10 minutes, until the crust is fragrant and set. Cool completely on a wire rack.
Make the Filling: In a medium bowl, whisk the egg yolks until foamy, about 30 seconds. Stir together the gelatin, sugar, ½ cup of the heavy cream and the salt in a medium saucepan and let sit until the gelatin softens, about 5 minutes. Cook over medium heat until the gelatin dissolves and the mixture is very hot but not boiling, about 2 minutes. Whisking continuously, slowly drizzle the gelatin mixture into egg yolks. Return mixture to saucepan and cook, stirring constantly, until slightly thickened, about 2 minutes. Remove from the heat and stir in the crème de menthe and crème de cacao. Pour into a large bowl and refrigerate, stirring every 5 minutes or so, until it thickens to a wobbly consistency, about 20 minutes.
Beat the remaining 1½ cups heavy cream on medium-high speed until it holds stiff peaks. Gently whisk 1 cup of the whipped cream into the gelatin mixture until completely incorporated. Using a rubber spatula, fold the remaining whipped cream into the gelatin mixture until no streaks of white remain. Scrape the mixture into the cooled pie shell, smooth the top, and refrigerate until firm, at least 6 hours or preferably overnight. Serve with whipped cream and topped with chocolate curls, if desired.
Notes
If you can’t find Cool Mint Oreos, you can use regular or homemade Oreos for the crust.
Use a glass cup or measuring cup to press the crust into the bottom of the pie plate to make sure it’s tightly packed.
Do I use the cookie and the cream filling, or just the cookie? You’ll want to use the whole Oreo to get the right consistency for the crust. Plus the mint filling in the cookie will add extra mint flavor to your grasshopper pie.
No-bake version of the crust: You can make the crust no-bake as well. Increase the butter amount to ¼ cup and make sure the crust is fully chilled before adding your filling.
Make-Ahead Crust: You can make the crust ahead of time (or several at once), then store them in the freezer for later use. If you’ll be storing for longer than a few days, cover with aluminum foil and then wrap the pie crust in plastic wrap. It should keep well frozen for 2 to 3 months.
Because the filling is no-bake, there is no way to cook off the alcohol. Please keep this in mind if you plan to serve it to children or anyone who can’t have alcohol.
To make a non-alcoholic version: Omit the creme de cacao and creme de menthe and replace with ½ teaspoon mint extract, 1 teaspoon vanilla extract, and ½ cup milk.
Storage: Store in the refrigerator for up to 4 days. Be sure to cover with plastic wrap to preserve flavor and keep it fresh.
Freezing Instructions: This pie freezes well! Wrap tightly in plastic wrap and aluminum foil and freeze for up to 3 months. You can slice and serve frozen, thaw in the refrigerator overnight, or allow to sit at room temperature for about 20 minutes before serving.