Begin by preheating your oven to 325 degrees F (165 degrees C). This ensures that the oven is at the right temperature when you're ready to bake your pie.

In a mixing bowl, combine the graham cracker crumbs and sugar until they are evenly mixed. Then, pour in the melted butter and stir until the crumbs are thoroughly coated.

Press this mixture firmly into the bottom and sides of a 9-inch pie plate to form the crust. Set the crust aside while you prepare the filling.

In a medium bowl, whisk together the sweetened condensed milk, fresh lemon juice, grated lemon zest, egg yolks, and salt until the mixture is smooth and well combined. Once mixed, pour this creamy lemon filling into the prepared crust, spreading it out evenly.

In another bowl, using an electric mixer, beat the egg whites and cream of tartar until soft peaks form. Gradually add in the sugar, continuing to beat until stiff peaks form and the meringue is glossy. Finally, mix in the vanilla extract to flavor the meringue.

Spread the prepared meringue over the lemon filling in the pie crust, making sure to seal it to the edges of the crust. You can create decorative peaks in the meringue using a spatula, if desired.

Place the assembled pie in the preheated oven and bake for 15 to 20 minutes, or until the meringue is lightly browned on top. Keep an eye on it to prevent over-browning.

Once baked, remove the pie from the oven and allow it to cool at room temperature for a while. Then, transfer it to the refrigerator and chill for at least 2 hours before serving. Chilling helps set the filling and allows the flavors to meld together.

Slice the chilled pie into servings and serve it cold. The delightful combination of tangy lemon filling and fluffy meringue topping is sure to impress your taste buds. Indulge in the magical flavors of this classic dessert with each bite!