Preheat the oven to 350°.

In a medium bowl, combine the butter, pecans, powdered sugar, and flour until it forms a shaggy dough. Press into a 9x13 baking dish and bake for 15 minutes, until golden brown and fragrant. Let cool completely.

Using the paddle attachment, beat the cream cheese until it’s smooth and fluffy. Add in the powdered sugar and vanilla. Once combined, fold in 8 ounces of whipped topping by hand until completely combined. Spread evenly over the cooled crust. Refrigerate for 10-15 minutes.

In a medium bowl, whisk the evaporated milk and pudding mix together until nice and thick. Spread it evenly across the cheesecake layer and place it in the fridge for 10-15 minutes, until the pudding has set.

Once the pudding is set, evenly spread the remaining 8 ounces of whipped topping over the top and sprinkle the chopped pecans and chopped pistachios over the top. Chill in the fridge for at least 3 hours before serving.