Directions

1. Preheat oven to 350°. Wrap the bottom half of a 9-in. springform pan with 3 layers of aluminum foil.
2. In a large bowl, combine graham crackers, sugar and melted butter. Press crumbs into the bottom of the pan and about 1 inch up the sides. Bake 8-10 minutes, until lightly browned. Set aside; cool to room temperature.
3. Increase oven temperature to 400°. In a large bowl, beat cream cheese on medium speed until smooth, 4-5 minutes. Reduce mixer speed to medium-low; add sugar and beat until fluffy. Add eggs, one at a time, until incorporated, about 5 minutes. Beat in pistachio butter, sour cream, lemon zest and vanilla extract until smooth and fluffy, 1-2 minutes. Pour filling into cooled crust.
4. Place springform pan in a larger baking pan; add 1 in. of hot water to larger pan. Bake 15 minutes. Turn oven down to 300°; bake until center is just set, 60-70 minutes longer. Turn oven off and open the oven door; let cheesecake sit 30 minutes, or until center is set. Remove from oven; let cool on wire rack up to 1 hour. Cover; refrigerate at least 6 hours or overnight.
5. In a chilled small glass bowl, beat cream until it begins to thicken. Add confectioners' sugar and vanilla; beat until soft peaks form. Store in the refrigerator until ready to use.
6. Remove sides of springform pan. Spread cheesecake with whipped cream; sprinkle with chopped pistachios. Slice and serve.