Prepare the crust: In a mixing bowl, combine graham cracker crumbs, sugar, and melted butter. Stir until well combined. Press the mixture into the bottom and up the sides of a 9-inch pie dish. Use the back of a spoon to pack it tightly. Refrigerate while preparing the filling.

1. Make the filling: In a large mixing bowl, beat together the softened cream cheese and sweetened condensed milk until smooth. Add in the fresh lemon juice, lemon zest, and vanilla extract. Mix until fully combined and smooth.
2. Make the whipped cream: In a separate bowl, beat the heavy whipping cream and powdered sugar with an electric mixer on high until soft peaks form. This should take about 3-4 minutes.
3. Combine the filling and whipped cream: Gently fold the whipped cream into the lemon mixture until well combined, creating a light and fluffy filling.
4. Assemble the pie: Pour the lemon filling into the chilled graham cracker crust. Use a spatula to smooth the top, ensuring it’s even.
5. Chill the pie: Refrigerate the pie for at least 4 hours, or until the filling is firm and set.
6. Serve: Once the pie is set, garnish with fresh lemon slices if desired, and serve chilled.