Line the bottom a 23cm/9" round springform baking pan with baking paper. Grease the sides with a small amount of butter. Break up Oreos and place in a food processor.
Add butter, 1 tablespoon of Nutella and blitz until it starts to clump.
Add 2-3 tablespoons of nuts in the food processor and pulse until you have a fine, sandy mixture.
Tip the mix into the springform pan and flatten evenly, making sure it reaches the edges. To flatten, you can use your hands, the back of a spoon (I use the tamp from our coffee machine).
Place in the fridge to chill.
In a bowl, beat the cream cheese and icing sugar until it is smooth.
Add the rest of the Nutella and continue beating until there are no more streaks.
Take the springform pan out of the fridge and carefully tip in the Nutella mixture over the Oreo base. 3
Smooth down with a spatula.
Sprinkle the remaining nuts evenly over the cheesecake. Cover the pan with tin foil and place in the fridge to set for at least 4 hours (preferably overnight).
Serve cold, straight from the fridge, with berries on the side.