Combine the gluten free flour, cornflour, xanthan gum and icing sugar in a large bowl
Rub in the dairy free spread until it resembles breadcrumbs
Mix in the egg yolks and water until the dough forms a ball
Wrap in cling film and chill in the fridge for 30 minutes

Preheat the oven to 180 oC
Divide the pasty in half
Roll out one of the pastry balls and line a 9″ deep pie dish with the pastry sheet
Bake the pastry blind (weighed down with baking beans) for ten minutes

Remove the beans and brush with the egg white
Bake for another 5 minutes

Make the pie filling by mixing together the blueberries, lemon juice, sugar and flour
Mix until well combined then place in the pastry case
Roll out the remaining pastry ball and place over the blueberry mix

Make a split in the middle of the pan or cut out some little shapes to allow the steam to escape during cooking
Brush with the egg white
Dust the top with a little caster sugar and cinnamon

Bake in the centre of the oven for 40 minutes
Remove and allow to cool slightly before serving