Preheat the oven to 325F and wrap the outside of a 9-inch springform pan with aluminum foil to prevent leaks.
In a medium bowl, combine the graham cracker crumbs, melted butter and granulated sugar for the crust. Press this mixture firmly into the bottom of your prepared pan.
Bake the crust for 10 minutes, then remove it from the oven and let it cool while you prepare the filling.
In a large mixing bowl, beat the softened cream cheese and granulated sugar using a hand mixer until totally smooth and creamy.
Scrape down the sides of the bowl with a spatula to ensure no lumps of cream cheese are left behind. Add the sour cream, heavy cream, cornstarch and vanilla extract to the bowl. Blend on a low speed just until the ingredients are fully combined.
Pour the smooth filling over your cooled graham cracker crust and spread it evenly to the edges.
Place the pan in the oven and bake for 60 to 70 minutes, until the edges are set but the center still has a slight jiggle.
Turn the oven off and leave the door slightly cracked, allowing the cheesecake to cool inside for one hour before chilling in the fridge overnight.
