Preheat oven to 350°F (175°C). Combine graham cracker crumbs, sugar, and melted butter. Press into the bottom of a 9-inch pie plate.
In a large bowl, beat cream cheese and sugar until smooth. Beat in pistachio paste and vanilla. Add eggs one at a time, mixing well after each addition. Stir in sour cream.
Pour filling into the prepared crust. Sprinkle with chopped pistachios.
Bake for 50-55 minutes, or until the center is set. Let cool completely before serving.
Notes
For a richer flavor, use unsalted pistachios and adjust the sugar to taste. Refrigerate leftovers for up to 3 days.