Flaky, all-butter golden pastry filled with a delicately spiced sweet filling, baked until crisp and aromatic.
Pulse flour, salt, and sugar in a food processor; add cold butter cubes and pulse until pea-sized crumbs form; drizzle ice water until dough just holds together; divide into two discs, wrap in clingfilm, and chill for 1 hour.
In a large bowl, toss apple slices with granulated sugar, dark brown sugar, flour, cornflour, cinnamon, nutmeg, and lemon juice; rest for 15 minutes.
Roll one dough disc to 30cm circle; fit into a 23cm deep pie dish; fill with spiced apple mixture and dot with 2 tbsp butter cubes.
Roll second dough disc and cut into 2cm wide strips; weave a lattice pattern over the apples, trim and crimp the edges firmly.
Brush lattice pastry with egg wash and sprinkle generously with coarse turbinado sugar.
Bake at 200°C for 20 minutes, then reduce heat to 180°C and bake for 45 minutes until crust is deep golden brown and apple juices bubble thickly.
Cool completely for 3 hours before slicing; serve with vanilla bean ice cream.