In a bowl, add graham cracker crumbs and granulated sugar. Stir to combine. Add melted butter and stir until fully incorporated. Using the back of a measuring cup, press graham cracker mixture firmly into bottom and sides of pie pan. Refrigerate while preparing filling.
In a large bowl, add cream cheese and beat until smooth. Add sweetened condensed milk and mix until combined. Then, add vanilla extract, lemon juice, and lemon zest. Mix until combined. Set aside.
In a separate bowl, whip heavy cream until stiff peaks form. Fold whipped cream into cream cheese mixture until just combined.
Pour filling into graham cracker crust and smooth the top with a spatula. Refrigerate until firm and chilled through, about 2 hours. Serve chilled and store any leftovers in the refrigerator.
This pie is even better the day after preparing - refrigerate overnight to allow the flavors to meld.
Pie will keep for 4-5 days covered in the refrigerator.
Pie must be prepared in a standard pie pan, not a springform pan.
Optionally, top your pie with additional lemon zest, graham cracker crumbs, or dollops of whipped cream.