01 - Preheat oven to 350°F. Prepare a 9x13-inch baking dish.
02 - In a medium bowl, combine the flour, softened butter, and powdered sugar. Mix until the texture becomes crumbly. Press the mixture firmly and evenly into the bottom of the baking dish.
03 - Bake for 18 to 20 minutes until the crust turns lightly golden. Remove from the oven and allow it to cool completely.
04 - Beat the softened cream cheese and powdered sugar together until perfectly smooth. Gently fold in 1 cup of whipped topping. Spread the mixture evenly over the cooled crust.
05 - In a large bowl, whisk together both packages of instant lemon pudding mix, cold milk, and lemon zest if using. Whisk vigorously for 2 minutes until the pudding thickens. Spread evenly over the cream cheese layer.
06 - Spread the remaining 2 cups of whipped topping gently over the lemon pudding layer, covering the entire surface.
07 - Refrigerate for at least 2 hours or until the layers are fully set and firm.
08 - Garnish with fresh lemon slices or a sprinkle of lemon zest before slicing into squares and serving.