Preheat oven to 350 degrees F

In a large bowl, add the flour and the cut up butter. Using a pastry blender or 2 knives, cut the butter into the flour until the mixture looks like small peas.

Stir in the walnuts

Press into a 13 x 9-inch pan.

Bake for 20 minutes.

Remove from oven and cool completely

Beat cream cheese, confectioner's sugar and the 1 cup of whipped topping until the mixture is smooth and silky.

Spread this across the cooled crust in the pan.

Prepare pistachio pudding by whisking it into the milk--whisking for 1-2 minutes until the pudding begins to thicken.

Spread the pudding on top of the cheese layer.

Chill for about 2-3 hours

Top with the 2 cups of whipped topping and sprinkle with toasted almonds (if using)