Add the whole Oreo cookies to a food processor and pulse into fine crumbs. Pour the crumbs into a bowl and stir in melted butter.
Press mixture evenly and firmly into the bottom and up the sides of a 9in pie dish. Bake for 10-12 minutes. Set aside to cool.
For the chocolate pudding filling:
To a medium sauce pan over medium heat, add the sugar, and milk and whisk well to combine. Bring mixture to a simmer, whisking frequently.
Meanwhile, add the egg yolks and cornstarch to a bowl and whisk until smooth.
Once the saucepan mixture is simmering, add a few spoonfuls of the hot liquid into the egg yolks and whisk to temper the eggs. Add a few more spoonfuls of the hot liquid into the egg yolks. Then slowly whisk the egg yolk mixture back into the saucepan. Whisk constantly until the mixture begins to thicken and comes to a very gently boil (big bubbles begin to break the surface).
Remove pan from the heat and whisk in the butter, chopped chocolate, and vanilla extract. Stir until completely smooth.
Pour filling into the cooled cookie crust and smooth into an even layer. Place a piece of plastic wrap gently on top and refrigerate until filling is set, about 4–6 hours or overnight, if desired.
For the topping:
Once pudding has set, make the topping by adding the cream to a mixing bowl. Mix with electric mixers on high speed for 1-2 minutes.
Add the sugar and vanilla extract. Continue mixing until soft peaks form, about 2-3 minutes.
Spread whipped cream over pie and top with chocolate curls or shavings.
Make ahead, storing and freezing: You can make this pie 1-2 days ahead of time. Store it gently covered in the refrigerator. The pie can be frozen for up to 3 months (although I feel it's taste and texture is not as beautiful after freezing). Allow to thaw overnight in the refrigerator before enjoying.Pie Crust: a traditional pie crust (be sure to blind bake it first), or a graham cracker crust could be substituted.Chocolate Curls: I've included step-by-step instructions in the post for making chocolate curls. Chocolate sprinkles, Oreo crumbs or fresh raspberries would also make a beautiful topping.