Step 1

Make pastry Place icing sugar, flour and butter into a food processor. Process until combined. Add 2 tablespoons of water. Process until pastry just starts to come together, adding more water if necessary.

Step 2

Turn pastry onto a lightly floured surface. Flatten into a disc. Wrap in baking paper. Refrigerate for 15 minutes.

Step 3

Preheat oven to 190°C. Dust a large sheet of baking paper with flour. Place pastry onto baking paper. Roll out to a 30cm (diameter) circle. Transfer pastry (still on baking paper) to a large baking tray. Whisk egg yolk. Brush pastry with egg yolk, leaving a 5cm border around edges. Sprinkle almonds over egg yolk. Arrange apple slices over pastry (leaving border free). Sprinkle with caster sugar.

Step 4

Fold pastry border in over apples. Lightly whisk eggwhite. Brush pastry edges with eggwhite. Sprinkle with demerara sugar.

Step 5

Bake for 15 minutes. Reduce oven temperature to 180°C. Bake for a further 15 minutes or until pastry is golden. Serve.