Prepare the crust: In a medium-sized mixing bowl, combine the finely crushed Oreo cookies with the melted unsalted butter. Stir until all cookie crumbs are fully coated in butter. Press this mixture firmly and evenly into the bottom of a 9x9 inch baking dish to form a solid crust. Place the dish in the refrigerator to chill while you prepare the cheesecake filling.
Make the cheesecake filling: In a large mixing bowl, use an electric mixer to beat the softened cream cheese until it reaches a smooth and creamy consistency. Gradually sprinkle in the sifted powdered sugar, mixing continuously until the sugar is fully absorbed. Add the pure vanilla extract and mix again until well combined and smooth.
Whip the cream: In a separate bowl, pour in the cold heavy whipping cream. Using an electric mixer, whip the cream until stiff peaks form. This means that when you lift the beaters out of the cream, it holds its shape and doesn’t collapse.
Incorporate the whipped cream: Gently fold the whipped cream into the cream cheese mixture, using a spatula. Be careful to maintain the light and airy texture of the whipped cream while blending it into the cheesecake filling.
Add chopped Oreos: Fold in the 10 roughly chopped Oreo cookies into the creamy filling, ensuring they are evenly distributed throughout the mixture for delightful cookie chunks in each bite.
Assemble the bars: Take the chilled crust from the refrigerator and carefully spread the cheesecake filling over the top, smoothing it out with a spatula to ensure an even layer.
Chill until firm: Cover the baking dish with plastic wrap and place it back in the refrigerator. Allow it to chill for a minimum of 4 hours, or until the cheesecake filling is set and firm to the touch.
Serve and garnish: After chilling, use a sharp knife to cut the cheesecake into rectangular bars. For added flavor and visual appeal, crumble extra Oreo cookies on top of each bar before serving, if desired.