Use a food processor to crush the 25 oreo cookies into fine crumbs, then slowly pour in the melted 6 tablespoons unsalted butter while the food processor is on low speed until the crumbs are evenly coated.
Firmly press the crumbs into the greased pie dish and place the crust in the freezer for 20 minutes.
Make the filling
Use an electric mixer to whip together 8 ounces cream cheese, 1/4 cup powdered sugar, 1 teaspoon vanilla extract, and 1/4 teaspoon salt in a large bowl until smooth.
Mix in the melted 4 ounces semi-sweet chocolate then fold in 4 ounces (or 1 cup) of whipped topping until it’s thoroughly mixed. Set aside.
In a medium bowl, whisk the 1 3.4-ounce box of instant chocolate pudding mix and cold 1 1/2 cup milk for 1-2 minutes or until the pudding starts to thicken. Let the pudding stand for 5 minutes to partially set.
Assembly
Spoon the chocolate and cream cheese mixture into the crust and spread it out evenly. Spread the chocolate pudding over the chocolate cream cheese layer, then smooth the remaining 8 ounces of whipped topping on top of the pie.
Chill
Cover the pie loosely with plastic wrap, and chill it in the refrigerator for 8 hours or overnight.
Serve
Top with chocolate shavings and serve chilled.
Notes
What to do with leftoversKeep any leftovers of your chocolate pie loosely covered in plastic wrap. If you're worried about ruining the top layer, stick a few toothpicks in the pie to help hold the plastic wrap up high enough so that it doesn't touch the surface.Substitutions/AdditionsMake things even easier and use a store-bought crust if you'd like.You can skip the whipped topping layer and give anyone who wants it, an individual dollop.Instead of shaved chocolate try crushed Oreos, crushed nuts, chocolate chips, or toffee bits. White chocolate would also be great!Freezing instructionsStore any leftover slices of chocolate pie, or the whole thing if you plan to freeze it just after assembling, in a freezer-safe airtight container. Be sure to give it the proper chill time in the fridge first.Then, keep it frozen for up to 2 months.