Preheat your oven to 350°F (175°C).

In a mixing bowl, combine the flour, softened butter, sugar, and salt. Mix until crumbly. Gradually add ice water (1 tablespoon at a time) until the dough comes together.

Roll the dough out to fit your pie dish and place it in the dish. Trim any excess dough hanging over the edges. Prick the bottom with a fork to avoid bubbling.

Bake the crust in the preheated oven for 15 minutes or until lightly golden. Remove from oven and allow to cool.

Meanwhile, prepare the lemon filling. In a saucepan, mix together sugar, cornstarch, and salt. Gradually whisk in water, then add the beaten egg yolks, lemon juice, and zest.

Cook the mixture over medium heat, stirring constantly until it thickens and begins to bubble. Once thickened, remove from heat and stir in the butter. Pour the filling into the baked pie crust.

To make the meringue, in a clean mixing bowl, beat the egg whites and cream of tartar until soft peaks form. Gradually add sugar, continuing to beat until stiff peaks form. Mix in vanilla extract.

Spread the meringue over the lemon filling, ensuring it touches the crust to prevent shrinking. Create peaks with the back of a spoon for a decorative effect.

Bake the pie in the oven for an additional 5-7 minutes or until the meringue is golden brown. Remove and let it cool to room temperature before serving.

Chill the pie in the refrigerator for a few hours for better slicing and flavor.