Oreo crust :

1. Blend the Oreo cookies in a food processor until finely powdered, then place in a medium bowl.
2. Add the melted butter and mix until smooth.
3. Pour the mixture into a 8 inches / 20 cm-diameter springform pan lined with parchment paper.
4. Press the oreo crust mixture down with the back of a tablespoon, starting at the bottom and working your way up the sides.
5. Place in the fridge for at least 30 minutes.

Cheesecake filling :

1. Whisk the cream cheese with the sugar until creamy.
2. Add the beaten eggs and whisk again to incorporate.
3. Add the vanilla extract, lemon juice and sour cream and beat again to incorporate.
4. Finally, using a flexible spatula, fold in the crushed Oreo cookies until smooth.
5. Pour the mixture over the Oreo crust in the prepared pan.

Baking

1. Preheat the oven to 300°F / 150°C and heat a medium saucepan of water to boiling.
2. Pour the hot water over the deep fryer positioned under the rack.
3. Place the Oreo cheesecake in the oven on the rack above the water pan and bake for 60-90 minutes, until firm in the center and slightly jiggly.
4. Turn off the oven and leave the Oreo cheesecake to cool for 1 hour, leaving the oven door open, then cool completely to room temperature before covering it with plastic wrap and refrigerating overnight.

Topping : 

1. Whip the cold mascarpone with the cold heavy cream, powdered sugar and vanilla extract with an electric mixer for around 3 minutes until stiff.
2. Place the whipped cream in a pastry bag fitted with a star tip.
3. Remove the cheesecake from the fridge and carefully unmold, then place on a serving dish.
4. Decorate the top of the cheesecake with the whipped cream and add Oreo cookie pieces.
5. Enjoy!