Heat oven to 180C/fan 160C/gas 4. Sift the flour and salt into a bowl. Cut the butter into small pieces and rub in until the mixture resembles fine breadcrumbs.
Mix in the sugar, lemon zest, egg yolk and a splash of milk to form a dough. Knead the dough lightly.
Spoon the apples and blackberries into a shallow 1.2ltr/900ml dish, then sprinkle over sugar to taste.
Roll out the pastry on a lightly floured surface, large enough to cover the pie. Place the pastry over the filled pie dish, then seal and flute the edges. Glaze the top of the pie with a little milk, then bake for 40-45 mins until golden.
Recipe courtesy of the 19 gales farmhouse shop. visit www.19gales.co.uk for more information