If you are using whipping cream, add powdered sugar and beat together using mixer until you get stiff peaks. Place whipped cream in a bowl, set aside.
Using mixer, beat cream cheese and powdered sugar until smooth and creamy. Add in remainder of lemon pudding, then add in lemon juice and lemon zest and mix together. Add in whipped topping and beat until all mixed together and spoon on top of lemon pudding.
Chill for 3 hours. Top with more whipped cream / lemon slices if desired.