In a food processor, pulse the oreos until they are fine crumbs. Add the melted butter. Pulse until evenly combined and resembling damp sand.
25 Oreos, 4 tablespoon butter
To form the crust, dump ⅔ of the crumbs in the bottom of a 9-inch deep dish pie pan. Using your fingers or a tamper, press the crumbs firmly into the side. Then add the remaining crumbs and press firmly into the bottom of the pan.
In a stand mixer fitted with whisk attachment or hand beaters, whip the heavy cream, powdered sugar and instant espresso on high until stiff peaks form, about 6-7 minutes.
3 cups heavy cream, ½ cup powdered sugar, 2 tablespoon instant espresso powder
Pour in the sweetened condensed milk and whip on low for 30 seconds, scrape well with a spatula, then whip on low for another 30 seconds.
14 oz sweetened condensed milk
Pour the filling into the prepared crust. Smooth out the top or add a design (see post for ideas). Then freeze uncovered for at least 6 hours. Once frozen thoroughly, cover with plastic wrap and leave in the freezer until ready to serve.
To serve, thaw for about 10 minutes to make it easier to cut. Enjoy!