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, or 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 completely smooth. Gently fold in the whipped topping. Spread the mixture evenly over the cooled crust using an offset spatula.
05 - In a large bowl, whisk together the instant lemon pudding mixes, cold milk, and lemon zest (if using) for about 2 minutes until thickened. Spread the pudding evenly over the cream cheese layer.
06 - Spread the remaining whipped topping gently and evenly over the lemon pudding layer.
07 - Refrigerate for at least 2 hours, or until the layers are fully set.
08 - Garnish with lemon slices or zest before slicing into portions and serving.