Preheat the oven to 375 degrees F.

Bake the pie crust for 9-11 minutes or until lightly golden brown. Allow to cool completely.

Stir together the sugar, cornstarch and salt in a saucepan. Then add the lemon juice and combine.

Add the lemon zest and egg yolks. Stir to combine.

Pour in water. Mix together.

Once combined, turn the heat to medium. Whisk continuously until the mixture starts to thicken. It will take 6-8 minutes.

After the mixture is the desired consistency, remove from heat.

Add butter and stir until melted, combined and smooth.

Pour this mixture into the cooled pie crust.

Then immediately make the meringue. You want the filling to still be warm when you add the meringue. I cover the pie with foil to make sure it stays warm while I make the meringue.

Use a stand mixer or hand mixer to beat the egg whites and cream of tartar for one minute on medium speed.

Once combined, increase the speed to high for 4 minutes until soft peaks form.

Next, add the sugar and salt to the mixture. Beat on high for 2 minutes.

Spread the meringue on top of the filing with a spatula or spoon. Make sure to spread the meringue all the way to the edge of the pie crust. This will help to prevent water from forming in between the filling and meringue that could make the pie watery. Use the back of the spoon to make peaks in the meringue.

Bake for 20-25 minutes in a preheated oven at 375 degrees on the lowest rack. If you notice the meringue is browning too fast, loosely cover the pie with foil (make sure that it does not touch the top of the pie).

Remove from the oven and allow to cool for 1 hour at room temperature. Then place in the fridge to set completely for 4 hours. Then the pie is ready to slice, serve and enjoy!