Place the shredded apples, sugar and cinnamon in a large saucepan.
Saute on medium heat for 10-15 minutes until softened. Set aside. When cooled and before spreading on the dough (see below) stir in the crushed cookies.
In the meantime, combine flour, baking powder and vanilla sugar in a large mixing bowl.
On low speed, beat in the butter. Avoid handling the dough too much as you want it to remain cold. If dough is too stiff, add 1-2 tbsp water to help it stick together.
Divide the dough into two gently formed logs, cover in plastic wrap and cool in fridge for 30 minutes.
Preheat oven to 350F. Working quickly, roll out log to cover the bottom of your baking pan and place it in the bottom of the pan.
Spread the cooled apple mixture evenly over the dough. Roll out the second log and gently place over the apple mixture. With a fork, poke some holes to allow steam to escape.
Bake in the center of the preheated oven for 30-40 minutes, until the top starts to turn golden. Once baked, let the pita cool before cutting into it, or it may fall apart.