Crush the cottage cheese with a fork, mix in the sour cream and the egg yolk, add salt to your taste. Beat the egg whites into a hard foam and mix it into the cottage cheese mass.
Spread oil on the filo pastry sheets. Spread a little cottage cheese mass in the baking tray, put a layer of pastry sheet on it, then comes some cottage cheese mass again, then grated cheese on the top. The layering is continued until you run out of pastry and filling, make sure that the top layer is pastry. Mix the oil into the milk and spread on top of the burek. Bake in a preheated 180-degree C oven until golden brown in 30 minutes.
It is best with some hearty, rich soup (e.g. bean soup, ragout soup, goulash soup).
Tip: For breakfast, you may offer Mizo natural yoghurt or Mizo Caucasian kefir with it. The filling can be minced meat or bolognese stew, ham or even sweet cottage cheese.