Pie time again - Lemon meringue

Pastry:
125g butter
250g plain flour
90g caster sugar
1 egg
iced water

Filling:
3 Tbsp cornflour
125g sugar
1/2 cup lemon juice
1 cup water
2 egg yolks
3 tsp grated lemon rind
30g butter

Meringue:
4 egg whites
90g sugar

Make pastry and chill for 30 mins.
Preheat oven to 220deg C.
Roll out pastry to fit 23cm pie dish. Prick sides and base and cook for 10 mins or until lightly browned. Set aside.
Make filling - mix cornflour, sugar and lemon juice in a saucepan over medium heat until smooth. Add water. Stir until thick. Remove and cool slightly. Whisk through egg yolks, lemon rind and butter. Pour into pastry case and chill for 1hr or until firm.

Make meringue - beat egg whites in clean bowl until stiff peaks form. Add sugar slowly until thick and glossy. Pile meringue on top of pie and bake at 160C for about 5 mins until meringue is light brown.