How to cook
Knead 1 egg, the oil, vinegar and flour into a medium hard dough. Make it into balls, each of which is rolled out on a floured worktop into a very thin crust for the pie. Roll out these pastry sheets, place flour between them and let them rest and dry for an hour.
Prepare a filling from the crushed feta cheese mixed with the beaten eggs and yoghurt, which are pre-dissolved with baking soda. Grease the tray, in which you will bake.
Each crust is either sprayed or coated nicely with hot oil, distribute filling along its length and roll it. Arrange along the wall of the tray, starting from the outside to the inside. Finally, distribute cubes of butter on the pie’s edges.
The Sofia-style phyllo pastry pie is baked in a heated oven at 392°F (200 °C) for 10-odd minutes, then reduce it to 302°F (150 °C) and bake until browned.