Crush the Oreo cookies into fine crumbs using a food processor or a zip-top bag and rolling pin. Mix crumbs with melted butter until fully combined. Press the mixture firmly into the bottom and up the sides of a 9-inch pie plate. Place in the freezer to set.

In a large bowl, beat the softened cream cheese with an electric mixer until smooth. Add the peanut butter and powdered sugar, and beat again until well combined. Scrape down the sides of the bowl as needed.

In a separate chilled bowl, whip the cold heavy cream and vanilla extract on high speed until stiff peaks form.

Gently fold the whipped cream into the peanut butter mixture until no white streaks remain. Be careful not to overmix. Spoon the filling into the chilled crust and spread evenly.

Cover the pie and refrigerate for at least 6 hours, or overnight, until firm. This step is crucial for the pie to set properly.