Make the pastry: In a large bowl, whisk together the flour, salt, and caster sugar. Scatter the frozen butter cubes over the flour. Using your fingertips, quickly rub the butter into the flour until the mixture looks like coarse breadcrumbs with some pea-sized butter pieces remaining. You should see distinct yellow flecks of butter — this is what makes the crust flaky.

Bring the dough together: Drizzle 120ml of the ice-cold water over the flour mixture. Stir with a butter knife or a spatula until the dough just starts to clump together. Squeeze a handful of dough — if it holds together without crumbling, it's ready. If it seems dry, add the remaining 30ml of water, one tablespoon at a time. Turn the dough onto a lightly floured surface, bring it together into a disc (don't knead), wrap in cling film, and pop it in the fridge for 15 minutes. Cue: The dough should feel cool and slightly tacky to the touch, not sticky.

Prep the apples: While the dough chills, peel, core, and slice the apples into 5mm thick slices. Place them in a large bowl. Add the brown sugar, cornflour, cinnamon, nutmeg, cloves, and lemon juice. Toss everything together with your hands until every slice is coated. Cue: You should hear a slight crunch as the sugar granules hit the apple, and the mixture will smell intensely of spiced citrus.

Roll out the base: On a well-floured surface, roll out two-thirds of the dough into a circle about 30cm in diameter. Carefully lift the dough by rolling it around your rolling pin, then unroll it into a 23cm pie dish. Gently press it into the bottom and up the sides. Cue: The dough should feel cold and firm; if it's getting sticky, pop it back in the fridge for 5 minutes.

Fill and top: Pile the apple filling into the crust, mounding it slightly in the centre. Roll out the remaining dough into a 28cm circle. Drape it over the filling. Pinch the edges of the top and bottom crusts together, then crimp them with your fingers or a fork. Cut 4-5 slits in the top to let steam escape. Cue: The pastry feels cool and pliable, and the apples are mounded high — they will shrink as they bake.

Bake to golden perfection: Brush the top crust with the beaten egg and sprinkle with the demerara sugar. Place the pie on a baking tray to catch any drips. Bake at 200°C (180°C fan) for 20 minutes. Then, reduce the oven temperature to 180°C (160°C fan) and bake for another 30-35 minutes. Cue: After 20 minutes, the crust should be a pale golden colour. At the end of baking, the crust will be a deep, glossy golden brown, and you should see thick, bubbly juice seeping through the slits. If the edges brown too quickly, cover them loosely with foil.

Cool before serving: Remove the pie from the oven and place it on a wire rack. Let it cool for at least 1 hour before slicing. Cue: You'll hear the pie gently crackling and settling as it cools. The filling will thicken as it rests, preventing a runny mess on your plate.