Prepare the dough: Mix flour, granulated sugar and salt in a bowl. Cut butter into cubes, add to dry mix and rub fingers into crumb.
Gradually pour in ice-cold water (5–7 tbsp. L.) In a bowl of dough, mixing it with a fork (start with a small amount and add if needed). When the dough starts to stick together, it means that there is enough water.
Wrap the dough in cling film, slightly leveling, and put it in the fridge to cool for 1 hour, or better for the whole night.
Prepare apple filling: peel the apples, remove the core and cut the pulp into slices.
Melt the butter in a large saucepan. Add apples to it and, stirring occasionally, add them for 2-3 minutes until softened.
Add boiled condensed milk to the apples, cinnamon and salt. In a bowl, dissolve the cornstarch in orange juice, pour it into a saucepan with apples and cook it all together on low heat, stirring constantly, for several minutes, until the mixture thickens. Completely cool the filling.
Preheat oven to 220 degrees.
For the creamy cinnamon filling, mix the butter with cinnamon and cardamom. Remove the dough from the refrigerator and divide it in half. On a floured table, roll one half of the dough into a 40×35 cm rectangle. Lubricate this part of the dough with an oil mixture and roll it into a roll on the long side. Repeat the same steps with the second half of the test. Put the rolls on a cutting board and put them in the freezer for 5–10 minutes.
Remove one roll from the freezer and cut it into slices about 1 cm wide. Place the bottom and sides of the baking dish with slices of creamy cinnamon filling, and then lightly press them so that they form a single dough piece. Remove the form with the workpiece in the freezer.
Remove the second roll from the freezer and cut it in the same way as the first (this time put the slices on baking paper in a circle (of sufficiently large diameter to form the top layer of the cake), and then lightly roll them). If the slices do not want to stick together, slightly moisten their sides with water.
Remove the base of the pie from the freezer and place the apple filling on it. Moisten the edges of the dough with water and cover the filling with the top layer of the cake. (The easiest way is to transfer this layer to the filling directly on the paper and then carefully remove it.) Cut off the excess hanging ends of the dough (you can not cut them off completely, but leave about 3 cm in length and decorate the edges of the cake with them). Put the cake in the freezer for 15 minutes so that it keeps its shape better during baking.
Remove the cake from the freezer. Prepare the mixture for lubrication: beat the egg with milk and salt. Brush with a mixture of cake and sprinkle with cane sugar.
Bake the cake on the lower level of the oven for 10 minutes, then reduce the temperature to 175 degrees and bake another 45-50 minutes until golden brown. Remove the finished cake from the oven and cool completely. Optionally served with vanilla ice cream.