Mix flour, 100 g sugar and salt in a bowl. Add butter in pieces and mix with your fingertips to a crumbly mixture. Add the egg and possibly 1 tbsp. cold water and knead to a smooth shortcrust pastry. Wrap in foil and chill for about 1 hour
Peel and quarter the apples and cut out the core. Cut apples into pieces. Sort the blackberries, wash carefully and drain well. Roughly chop the nuts. First mix apples, lemon juice, orange peel and 60 g sugar, then fold in blackberries and nuts
Roll out approx. 2/3 of the dough on a lightly floured sheet of baking paper to form a circle (approx. 32 cm Ø) and line a greased pie tin (approx. 24 cm Ø/ approx. 4 cm high rim) with it. Sprinkle breadcrumbs on the dough base and add the apple-blackberry mixture
Roll out the remaining dough to a rectangle (approx. 24 cm long) about 0.4 cm thick. Use a dough wheel to cut it into strips about 1 cm wide and lay them on the fruit as a grid. Press the edges well. Mix egg yolk and milk and brush the dough grid with it. Bake in the preheated oven, lower shelf (electric oven: 200 °C/ convection oven: 175 °C/ gas: level 3) for 30-40 minutes. Dust with icing sugar as desired and serve warm. Delicious with vanilla sauce
Waiting time approx. 30 minutes