Step 1: Make the Pastry

• Mix the flour and butter: In a large mixing bowl, rub the cold cubed butter into the flour until the mixture resembles fine breadcrumbs.
• Add the sugar and water: Stir in the caster sugar, then gradually add cold water, one tablespoon at a time, mixing until the dough comes together. Be careful not to overwork the dough.
• Chill the pastry: Wrap the dough in cling film and refrigerate for 20-30 minutes.

Step 2: Prepare the Apple Filling

• Slice the apples: Peel, core, and slice the cooking apples. Place them in a bowl and toss with the lemon juice to prevent browning.
• Add sugar and cinnamon: Sprinkle the caster sugar and cinnamon over the apple slices and mix to coat the apples evenly.

Step 3: Roll Out the Pastry

• Roll out the pastry: On a lightly floured surface, roll out two-thirds of the pastry to fit your 23cm pie dish. Press the pastry into the dish, trimming any excess.
• Fill with apples: Add the apple mixture to the pastry-lined dish, spreading it evenly.

Step 4: Add the Top Crust

• Roll out the remaining pastry: Roll out the remaining third of the pastry for the top crust. Drape it over the apples, sealing the edges with your fingers or a fork.
• Crimp and glaze: Crimp the edges to seal the pie and cut a few small slits in the top to allow steam to escape. Brush the top with beaten egg for a golden finish.

Step 5: Bake the Pie

• Bake: Preheat the oven to 190°C (170°C fan)/375°F/gas mark 5. Bake the pie for 35-40 minutes, or until the pastry is golden brown and the apples are tender.
• Cool slightly: Allow the pie to cool for a few minutes before slicing and serving.