Classic Lemon Meringue Pie

Prepare the Pie Crust
In a large bowl, mix flour, sugar, and salt.
Cut in cold butter with a pastry cutter or fingers until mixture resembles coarse crumbs.
Add ice water 1 tbsp at a time, mixing until dough just holds together.
Shape into a disk, wrap in plastic, and chill 30 minutes.
Roll out and fit into a 9-inch pie pan. Prick the bottom with a fork.
Bake at 375°F (190°C) for 15–20 minutes until lightly golden. Let cool.
Make the Lemon Filling
In a medium saucepan, whisk sugar, flour, cornstarch, and salt.
Gradually stir in water, lemon juice, and zest.
Cook over medium heat, stirring constantly, until thick and bubbly.
Reduce heat; stir in butter.
In a small bowl, whisk egg yolks. Gradually whisk in a few spoonfuls of hot lemon mixture (tempering).
Return yolk mixture to saucepan; cook 2 more minutes, stirring constantly. Remove from heat.
Pour filling into baked pie crust.
Whip the Meringue
In a clean bowl, beat egg whites and cream of tartar until soft peaks form.
Gradually add sugar, 1 tbsp at a time, until stiff, glossy peaks form.
Beat in vanilla extract.
Top & Bake
Spread meringue over hot lemon filling, sealing edges to crust.
Bake at 350°F (175°C) for 10–15 minutes, until meringue is golden brown.