Place cheese, butter and flour in a bowl and mix together with a pastry blender. Gradually add water until forming a firm dough. Knead lightly, cover with waxed paper and place in refrigerator to rest for 1/2 hour. Once rested, roll out to 1/4-inch thick oblong shape. Divide dough in 1/2 to make 2 squares, reserving 2 (1-inch) square pieces. Place large sheets of dough side by side on cookie sheet.
Preheat oven to 375 degrees F. Peel and core apples. With syringe, inject apples with Kirsch and fill cavity with Camembert. Place apples on dough and top with Emmenthal. Pull opposite corner of pastry together on top of apple, crimp and seal, securing edges tightly with beaten egg. Cover seams with reserved patches of pastry. Add pinch salt to remaining egg wash and brush pastry. Bake for 30 minutes, until crisp and golden brown.
Created by Graham Kerr for the Zurich Railway Station