Pulse the Oreos in a food processor until fine crumbs form. If you don’t have a food processor, place the Oreos in a zip-top bag and crush them with a rolling pin or cup until very fine.
In a mixing bowl, combine the Oreo crumbs, espresso powder, and melted butter. Mix until all the crumbs are coated.
Press the mixture firmly and evenly into the bottom of the prepared pan. Transfer the pan to the freezer to firm up while you make the filling.
Remove the crust from the freezer and spread ⅓ of the cheesecake filling over the crust in an even layer.
Quickly dip each ladyfinger into the espresso (add Kahlúa if using), dipping for less than a second so they don’t get too soft. Arrange the dipped ladyfingers in an even layer over the filling.
Spread a thin layer of cheesecake filling over the ladyfingers to cover them.
Transfer the remaining cheesecake filling to a piping bag fitted with a star tip and pipe dollops all over the top of the cheesecake.
Cover the pan with plastic wrap and refrigerate for at least 4 hours, or until fully set and the ladyfingers have softened.
Remove from the fridge, release the cheesecake from the springform pan, and transfer to a serving plate.
Dust generously with cocoa powder, slice, and enjoy!
Notes
Use room-temperature cream cheese and mascarpone. Soft cream cheese blends smoothly and prevents lumps. Cold cheese will create a grainy mixture that won’t turn creamy.
Use COLD heavy cream. Cold cream whips faster, holds its shape better, and gives the cheesecake a stable, fluffy texture. Room-temperature cream won’t whip as well.
Chill the mixing bowl. To help the cream whip even faster, place your mixing bowl in the freezer for about 10 minutes before whipping.
Use a nonstick springform pan. This makes it easy to release the cheesecake cleanly without damaging the edges.
Don’t overmix the filling. Over-whipping can cause the mixture to curdle or become too soft to set properly. Mix just until smooth and creamy.
Use full-fat cream cheese. High-fat cream cheese (like Philadelphia) gives the cheesecake structure and the best flavor. Low-fat versions won’t set as well.
Let the cheesecake set fully. Chill the cheesecake for at least 5 hours, preferably overnight. This helps it firm up and gives the flavors time to develop.
Scrape the bowl often. Frequently scraping down the sides ensures the mixture stays smooth and lump-free.
Dip ladyfingers quickly. A super quick dip (less than 1 second) keeps them soft but not soggy, so the layers hold their shape.
Dust the cocoa right before serving. This keeps the cocoa powder fresh, dry, and beautiful on top of the cheesecake.