In a mixing bowl, combine graham cracker crumbs, ground pistachios, and granulated sugar. Pour in melted butter and mix until the texture resembles wet sand. Press into a greased 9-inch springform pan. Bake at 350°F for 5-8 minutes until lightly golden, then cool completely.

Lower the oven temperature to 280°F. Beat cream cheese and granulated sugar together in a large mixing bowl until creamy. Gradually add sour cream, heavy cream, vanilla extract, and salt, mixing until well combined.

Add pistachio paste and cornstarch to the mixture, stirring until fully incorporated. In a separate bowl, whisk the eggs lightly and add them one at a time to the filling, mixing gently after each addition.

Pour the cheesecake batter over the cooled crust and spread evenly. Bake at 280°F for about 1 hour until the edges are set and the center remains slightly jiggly.

Turn off the oven and crack the door open to cool the cheesecake gradually for 1-2 hours. Wrap in plastic wrap and refrigerate for at least 5 hours or overnight.

Melt white chocolate, pistachio paste, and heavy cream together until smooth. Stir in chopped pistachios.

Once set, remove the cheesecake from the springform pan and spread the pistachio topping evenly on top. Chill briefly to set before serving.