1. Dice butter into pea-size and pop in freezer for about 10mins.
2. In a food processor mix flour, salt and sugar. Then pop in frozen butter and pulse until you get crumbs. You can rub the butter into the flour mixture with your hands (this will be fun to do with your kids). Just do it quickly so the butter won't melt in the heat.
3. Add in water bit by bit as you pulse until the dough just about comes together when you pinch it. Add a bit more water if needed.
4. Take out dough on a clean surface and press it together into a ball.
5. Wrap clingfilm around it and pop it in the fridge while you make the filing.
6. Core and chop apples into chunky squares.
7. Heat butter, put in apples, cranberries, sugars, cinnamon and salt. Let it cook until apple turns nice and soft. Taste and add more salt or sugar if needed.
8. The apple will release water so thicken everything up by adding the cornflour. Cool it down in the fridge for half an hour.
9. Roll out dough on a cool surface and cut round shapes. Put filling on a dough round, brush egg on the sides and cover it with another dough round. Crimp the sides with a fork. Brush egg on top and sprinkle some sugar.
10. Bake in 200c oven for about 20-25 minutes until golden brown.
11. You can also push down a dough round in a muffin tin, fill it and put little strips of dough on top for a more rustic pie.