1. Prepare pastry. Rub the butter with the flour until crumbly. After the butter and flour are in crumbs, add in a pinch of salt and a few tsp of water and hold the crumbs together to form a firm dough. Wrap and rest in fridge 15-20 minutes.
2. Boil raisin with water till water fully absorbed.
3. Mix (A) with diced apples.
4. Roll 1/2 dough to line base of pie tin. Brush with egg white.
5. Spoon pie fillings into pastry lined tin.
6. Roll remainder 1/2 dough to cover top of pie.
7. Cut slits on top of pie to allow steam to escape. Make sure the slits are big enough because the dough tends to stick together again if the slits are small.
(You can add decorations like leaf-shapes with any extra pastry)
8. Brush top with egg, pinch edge of pie well.
9. Sprinkle with castor sugar over top if desired.
10. Bake in preheated oven at 375°F/190°C for 35 minutes till pie is golden brown.