Step 1: Make the shortcrust pastry

• In a mixing bowl, rub the chilled butter into the flour with your fingertips until the mixture resembles breadcrumbs.
• Stir in the caster sugar, then add cold water, one tablespoon at a time, until the dough comes together.
• Roll the dough into a ball, wrap it in cling film, and refrigerate for 30 minutes.

Step 2: Preheat the oven

• Preheat your oven to 180°C (350°F).

Step 3: Blind bake the pastry

• Roll out the chilled pastry on a floured surface and line a 23cm pie dish.
• Trim the edges and prick the base with a fork. Line with baking paper and fill with baking beans.
• Blind bake the pastry for 15 minutes, then remove the beans and paper, and bake for another 5 minutes until golden and crisp.
• Set aside to cool while preparing the filling.

Step 4: Make the lemon filling

• In a saucepan, combine the lemon juice, zest, caster sugar, and cornflour with 300ml of water.
• Stir over medium heat until the mixture thickens and comes to a boil.
• Remove from heat, and whisk in the egg yolks and butter until smooth.
• Pour the lemon filling into the cooled pastry shell.

Step 5: Prepare the meringue

• In a clean mixing bowl, whisk the egg whites to soft peaks using an electric mixer.
• Gradually add the caster sugar, one spoonful at a time, while whisking, until the meringue is glossy and holds stiff peaks.
• Fold in the cornflour gently to stabilize the meringue.

Step 6: Top with meringue and bake

• Spoon the meringue over the lemon filling, spreading it to cover the filling completely. Create peaks and swirls with the back of a spoon.
• Bake the pie in the oven for 15-20 minutes until the meringue is golden and crisp on top.

Step 7: Cool and serve

• Let the pie cool completely before slicing to allow the lemon filling to set.
• Serve as a delightful dessert with a hot cup of tea or coffee.