Crust

1. Crush the Oreos (whole, cream included) in a food processor until finely ground. Stir in melted butter until the mixture resembles wet sand. Press evenly into the bottom of a square pan and chill in the freezer for about 10 minutes to firm up.

Cheesecake filling

1. In a mixing bowl, work the cream cheese with Nutella using a spatula until smooth and fully combined.
2. In a separate chilled bowl, whip the heavy whipping cream with powdered sugar until soft peaks form.
3. Gently fold the whipped cream into the Nutella and cream cheese mixture until fully combined and smooth.

Assable

1. Spread half of the cheesecake filling evenly over the prepared crust and smooth the surface.
2. Melt some Nutella and spread it gently over the first cheesecake layer, keeping it as a thin ribbon or middle layer.
3. Add the rest of the cheesecake filling and smooth the top evenly.
4. Refrigerate for at least 8 hours, or overnight, until the cheesecake is completely firm.

Decorate

1. Melt more Nutella and pour it over the set cheesecake, tilting the pan gently to spread it evenly. Refrigerate or freeze for about 10 minutes to set the top layer.
2. Remove from the pan carefully, then slice into squares using a sharp knife. Wipe and warm the knife between each cut for clean edges.