Pistachio Pineapple Delight

In a medium bowl, combine the graham cracker crumbs and melted butter until the crumbs are evenly moistened and the mixture resembles wet sand. Press this mixture firmly into the bottom of a 9x13-inch baking dish to form an even crust.
In a large mixing bowl, use an electric mixer on medium speed to beat the softened cream cheese and powdered sugar together until the mixture is completely smooth and free of lumps, about 2 minutes.
Spread the cream cheese mixture evenly over the prepared graham cracker crust, creating a smooth layer.
In another large bowl, whisk together the instant pistachio pudding mix and cold milk for 2 minutes, until the pudding begins to thicken. Gently fold in the thoroughly drained crushed pineapple until just combined.
Carefully spread the pistachio-pineapple mixture over the cream cheese layer. Cover the dish and refrigerate for at least 4 hours, or until the dessert is completely set and firm.
Just before serving, spread the thawed whipped topping over the chilled dessert and sprinkle the chopped pistachios evenly over the top as a garnish.