In a food processor or zip-top bag, crush Oreo cookies into fine crumbs. Mix crumbs with melted butter until evenly coated. Press firmly into a 9‑inch pie pan to form the crust. Chill in the freezer while preparing filling.

In a heatproof bowl over simmering water (double boiler), melt chocolate and heavy cream together, stirring until smooth. Remove from heat and let cool slightly.

In a medium bowl, beat cream cheese, powdered sugar, and vanilla until smooth and fluffy.

Fold the cooled chocolate ganache into the cream‑cheese mixture until fully combined. Spread the filling evenly into the chilled Oreo crust.

Cover and refrigerate for at least 4 hours or overnight, until set.

Before serving, top with whipped cream, sprinkle chopped nuts evenly, and drizzle chocolate sauce over the top.

Slice with a warm, damp knife for clean cuts.