Preheat the oven to 325F degrees and lightly grease a 9-inch pie plate.

In a medium bowl stir together the graham crumbs, sugar and melted butter.

Press into the bottom and up the sides of the pie plate to form the crust. Then pop it in the freezer as you make the filling.

In a large bowl whisk together the lemon juice and sweetened condensed milk.

In a separate large bowl beat together the egg yolks and lemon zest until frothy and lighter in color.

Then gently mix in the sweetened condensed milk and lemon juice.

Pour the mixture into the pie crust and bake for 25-30 minutes or until the top looks set and there's a slight wobble in the middle.

Allow to cool at room temperature, then chill in the fridge or freezer for at least 6 hours to set.

Top with whipped cream to serve.