1. In a medium bowl, beat sweetened condensed milk, lemon juice and zest combined. Fold in whipped topping. Spoon filing into a large piping bag or gallon-size zip-top bag, and snip off a small corner.

2. Place a Nilla wafer in the bottom of a push-pop container and squeeze a dollop of lemon filling on top. Continue layering cookies and filling until you fill up your container, making sure to finish with a dollop of the lemon filling on top.

3. Chill all of the containers for at least 6 hours, but preferably overnight.