Preheat oven to 400 degrees.
Mix sugar and cornstarch in medium saucepan.
Gradually stir in water.
Cook over medium heat, stirring constantly until mixture thickens and boils.
Boil and stir for 1 minute.
Remove from heat.
Stir in butter, lemon peel and lemon juice.
Temper in the egg yolks slowly.
Pour into baked pie shell.
Heap meringue onto hot pie filling.
Spread over filing and seal meringue to edge of pie crust to prevent shrinking or weeping.
Put peaks in the meringue using back of a spoon and lifting upwards.
Bake for about 10 minutes or until a delicate brown.
Cool away from drafts.
