Mix graham crackers, sugar and melted butter and pat down into 7-9 inch springform pan.
Push the crust down with a measuring cup to pack the crust down. Freeze while preparing the cheesecake filling.
Cream together cream cheese and sugar until smooth, with a hand-held mixer.
In a standing mixer, whip heavy cream until thick.
Stir whipped cream and vanilla into the cream cheese and sugar mixture until smooth.
Pour the cheesecake filling onto the crust, and smooth out the top.
Scoop Nutella onto the top of the cheesecake and swirl around to cover the top.
Refrigerate for 12 hours (or overnighbefore serving.
To make the springform pan release easier (and for easier slicing), freeze for 15-20 minutes before serving.
Top with banana slices and serve.