How to make
Put the baking soda in the yoghurt to bubble. In a bowl, beat the eggs and add the effervescent yoghurt to them. Melt the butter and smear the oven dish in which you intend to bake with part of it.
Add the rest of the butter to the bowl with the egg mixture. Add the crumbled feta cheese to it too. Stir everything well.
Arrange the phyllo pastry sheets in the oven dish, in a harmonica arrangement. The sheets need to look equally wavy throughout. Slightly ruffle each sheet, without ripping it and place it on. Once you've arranged all of the sheets in the oven dish, pour the filling evenly on top.
Bake in a preheated 360°F (180 °C) oven about 30-40 min. until it gains a beautiful golden color.
Once you take it out of the oven, sprinkle it with a little cold water and cover the oven dish with a paper towel on top. After 5 min., you can cut the phyllo pastry and serve.