1. Preheat oven to 325°F (163°C). Line a 9-inch (23cm) springform pan with parchment paper in the bottom and grease the sides.
2. Combine the crust ingredients in a small bowl. Press the mixture into the bottom and up the sides of the springform pan.
3. Bake the crust for 8-10 minutes, then set aside to cool.
4. Cover the outsides of the pan with aluminum foil so that water from the water bath cannot get in (see how I prepare a pan for a water bath). Set prepared pan aside.

FILLING

1. Reduce oven temperature to 300°F (148°C).
2. In a large bowl, beat the cream cheese, sugar and flour on low speed until well completely combined and smooth. Be sure to use low speed to reduce the amount of air added to the batter, which can cause cracks. Scrape down the sides of the bowl.
3. Add the Nutella and vanilla extract and mix on low speed until well combined.
4. Add the eggs one at a time, mixing slowly to combine after each addition. Scrape down the sides of the bowl as needed to make sure everything is well combined. The batter will be thick and a little sticky.
5. Pour the cheesecake evenly batter into the crust.
6. Place the springform pan inside another larger pan. Fill the outside pan with enough warm water to go about halfway up the sides of the springform pan. The water should not go above the top edge of the aluminum foil on the springform pan.
7. Bake for 1 hour 30 minutes. The center should be set, but still jiggly.
8. Turn off the oven and leave the door closed for 30 minutes. The cheesecake will continue to cook, but slowly begin to cool as well.
9. Crack the door of the oven for 30 minutes to allow the cheesecake to continue to cool slowly. This process helps prevent cracking.
10. Remove the cheesecake from the oven and water bath wrapping and refrigerate until firm, 5-6 hours or overnight.
11. Remove the cheesecake from the springform pan and place on a serving dish.
12. To make the Nutella ganache, add the Nutella, chocolate chips and heavy whipping cream to a medium bowl. Heat in 15-20 second increments, stirring well between each, until the mixture is melted and smooth. Allow it to cool for 5-10 minutes
13. Pour about half of the ganache into the center of the cheesecake and lightly help it spread mostly to the edge of the cheesecake. It will continue to spread a little as it cools. Save the remaining ganache for later.
14. Refrigerate until the ganache is firm, then make the chocolate whipped cream.
15. Add the heavy whipping cream, cocoa powder, powdered sugar and vanilla extract to a large mixture bowl and whip on high speed until stiff peaks form.
16. Pipe the whipped cream around the outer edge of the cheesecake, then finish it off with a drizzle of some of the remaining ganache and Ferrero Rocher candies. If you have ganache remaining, serve it with the cheesecake slices.
17. Refrigerate the cheesecake until ready to serve. Cheesecake is best if eaten within 3-4 days.