01 - Preheat oven to 350°F. Prepare a 9x13-inch baking dish by lightly greasing or lining it.
02 - In a medium bowl, combine the flour, powdered sugar, and softened butter. Mix until the mixture becomes crumbly and resembles coarse sand. Press the mixture evenly and firmly into the bottom of the prepared baking dish. Bake for 12 to 15 minutes, or until the crust is lightly golden around the edges. Remove from the oven and allow it to cool completely.
03 - In a separate bowl, beat the softened cream cheese with an electric mixer until completely smooth and free of lumps. Gradually add the powdered sugar while continuing to mix. Gently fold in the whipped topping until well combined. Spread this mixture evenly over the fully cooled crust.
04 - In a bowl, whisk together the instant lemon pudding mix, cold milk, and fresh lemon juice for 2 to 3 minutes until the mixture thickens to a pudding consistency. Spread the lemon pudding evenly over the cream cheese layer.
05 - Spread the remaining whipped topping in an even layer over the lemon pudding. Smooth the top with a spatula.
06 - Refrigerate for at least 2 hours, preferably overnight, to allow all layers to set properly. Before serving, garnish with fresh lemon zest if desired. Slice into squares and serve chilled.