Crush 20 Oreo cookies into fine crumbs using a food processor or by placing them in a sealed bag and crushing with a rolling pin until you have about 2 cups of crumbs.

Mix the cookie crumbs with melted butter in a medium bowl until the mixture resembles wet sand. Press firmly into the bottom of a 9-inch springform pan using the bottom of a measuring cup. Refrigerate while you prepare the filling.

Beat the softened cream cheese in a large bowl with an electric mixer on medium speed for 2 minutes until completely smooth and fluffy with no lumps remaining.

Add granulated sugar and vanilla extract to the cream cheese, then beat for another minute until fully incorporated and the mixture looks light and creamy.

In a separate chilled bowl, whip the cold heavy cream and powdered sugar together on high speed for 2-3 minutes until stiff peaks form and the cream holds its shape when you lift the beaters.

Gently fold half of the whipped cream into the cream cheese mixture using a rubber spatula, then fold in the remaining whipped cream until no white streaks remain. Fold in the 8 coarsely chopped Oreos.

Pour the filling over the chilled crust and smooth the top with an offset spatula. Crush the remaining 4 Oreos and sprinkle over the top, gently pressing them into the surface.

Cover loosely with plastic wrap and refrigerate for at least 4 hours or overnight until firm enough to slice cleanly. Run a thin knife around the edges before releasing the springform pan sides.

Just before serving, pipe or dollop whipped cream around the edges and garnish with extra Oreo halves if desired. Slice with a hot, clean knife for the cleanest cuts.