For the crust: In a food processor or in a zipped plastic bag using a rolling pin crush wafers. You will need 2 cups crushed wafers.

In a bowl mix the crushed wafers, melted butter and sugar until combined. Firmly press mixture into bottom of an 8-inch square pan and slightly up sides. Chill, until ready to fill.

For the filling: Using an electric mixer beat cream cheese until smooth. With mixer running on low, add condensed milk a little at a time, scraping down sides of bowl as needed. Beat in lemon juice and vanilla extract.

Remove crust from fridge, pour in filling and crumble additional wafers over the filling. Cover with plastic wrap and place in fridge until firm, about 3 hours or overnight.