Blitz biscuits in the food processor till fine crumbs. Melt butter and add to the biscuit crumbs. Mix till you get a fine sand consistency and pour it into a 8 inch springform tin. Using a spatular, compact the biscuit crumbs to form a nice crunchy base for the cheesecake. Freeze for 40 minutes.
Mix 3 tsp gelatine and 3 tbsp water. Once well mixed, set aside and let the gelatine bloom. In a large bowl, whisk 200ml heavy cream until stiff peaks.
In another large mixing bowl, whisk 500g softened cream cheese and 400g Nutella until well combined. Make sure to scrape down sides to mix well. (Note: the Nutella mixture may be a little grainy at first). Add the whipped cream to the Nutella cheese mixture and mix gently with a spatula to combine. Once evenly mixed, liquefy/microwave the gelatine with some cream for 5 seconds and mix it in. The Nutella cheese mixture is done.
Using a wooden skewer, gently poke numerous holes in the biscuit base (this helps to hold the cheese mixture well) and then pour in the Nutella cheese batter. Use the skewer to run through the cheese batter several times and to spread it evenly to the edges of the tin. Chill for 5 hours or overnight.
Just before serving, using a thin knife, gently run through the edges of the springform tin for easy un-moulding. Un-mould and transfer the cheesecake onto a plate. Decorate with the gorgeous spiky candied nuts. Serve and enjoy.