In a mixing bowl, combine the vanilla wafer crumbs, granulated sugar, and salt. Pour in the melted unsalted butter, stirring until the mixture resembles wet sand. Press this mixture firmly into the bottom and up the sides of a springform or cheesecake pan, ensuring it's even. Place the crust in the refrigerator to chill for 30 minutes.

In a large mixing bowl, beat the room temperature cream cheese until smooth and creamy, about 2-3 minutes. Gradually mix in the instant pistachio pudding mix, vanilla extract, pistachio extract, and powdered sugar, blending until fully combined. Slowly add in the heavy cream, continuing to mix until the filling is light and fluffy, which should take an additional 2-3 minutes.

Take the chilled crust out of the refrigerator and spoon the pistachio filling into it, using an offset spatula to smooth the top evenly. Cover the cheesecake with plastic wrap and place it in the refrigerator to chill for at least 6 hours.

In a separate mixing bowl, combine the heavy cream, powdered sugar, and a splash of vanilla extract. Beat on medium speed until stiff peaks form, which takes about 3-5 minutes. Once the cheesecake has set, gently spread or pipe the whipped cream topping over the chilled cheesecake.

Sprinkle the top of your No Bake Pistachio Cheesecake with the chopped pistachios for added crunch. Slice the cheesecake into wedges and serve chilled.