For the filling, whisk the eggs and add the yoghurt and crumbled feta cheese. Grate the cheese and melt the butter. Put 1 phyllo pastry sheet on the kitchen counter and brush it with butter. Add another phyllo pastry sheet on top and butter once again.
Sprinkle with a bit of stuffing and a little cheese. Wrap the phyllo pastries into rectangles and arrange them in a tray. Brush the top with plenty of butter and optionally sprinkle a little more cheese.
Prepare the remaining phyllo pastries in the same manner. Bake them in a heated 356°F (180 °C) oven until they get a nice tan, or for about 25-30 minutes.