In a food processor, pulse the Oreos until they turn into fine crumbs. Melt the butter and mix it with the crushed Oreos. Press the mixture into a 9-inch pie pan.

In a stand mixer, combine the cold heavy cream, powdered sugar, and instant espresso powder. Beat on high speed for 6-7 minutes or until stiff peaks form.

Gently fold in the sweetened condensed milk into the whipped mixture. Mix on low speed for 30 seconds, and scrape down the bowl sides. Blend again for another 30 seconds until smooth.

Pour the creamy filling into the prepared Oreo crust, smoothing the top. Cover loosely and freeze for at least 6 hours until solid.

Once frozen, let the pie sit at room temperature for 10 minutes. Use a sharp knife dipped in hot water to slice and serve chilled.