In a mixing bowl, combine the crushed Oreo cookies and melted butter until well blended. Press the mixture firmly into the bottom of a 9x9-inch square baking dish to create the crust. Refrigerate while preparing the filling.
In a large mixing bowl, beat the softened cream cheese until smooth. Slowly add powdered sugar and vanilla extract, mixing until fully incorporated and creamy.
In a separate bowl, whip the heavy whipping cream until stiff peaks form. Gradually fold the whipped cream into the cream cheese mixture until well combined, being careful not to deflate the whipped cream.
Fold in the chopped Oreo cookies gently into the cheesecake filling.
Pour the cheesecake mixture over the chilled Oreo crust, spreading evenly. Smooth the top with a spatula.
Cover the baking dish with plastic wrap and refrigerate for at least 4 hours, or until the cheesecake is set.
Once set, slice into bars and serve. Drizzle with chocolate sauce if desired, and top with additional Oreo pieces for extra crunch and decoration.