Combine in a large bowl using a pastry blender or a fork, 300 grams of flours, butter, 100 grams of sugar, the egg and the vanilla and the salt.
Finish the dough by hand. Form the dough into a disc and wrap in saran wrap and refrigerate for at least 2 hours. It’s very important to work with cold dough.
In a large bowl, toss apples in lemon juice, 20 grams flour, and the brown sugar. Set aside.
Divide the pie dough in two; roll out the first half and cover the pie form, and add the apple mix.
Roll out the remaining pie dough. Cut into strips 2 cm. Place one layer of strips across the pie, over the apples, spacing strips about 1 cm apart. Do not press the edges down.
Bake for 30-35 minutes, or until the top is golden brown and juices are bubbling. Served with vanilla ice!