How to make
Put the yoghurt, baking soda and salt in a large bowl. Stir and wait for the mixture to bubble. Add the egg and stir once again. Gradually add the flour while stirring with a wooden spoon.
Add the crumbled feta cheese to the mixture and stir once more. Pour the mixture into a small, oiled oven dish. Smooth it out with a spoon and smear with the egg beaten with the olive oil.
Cover the loaf with grated cheese. Put it to bake in a preheated 270°F (130 °C) oven. Once it crisps a bit, turn it up to 360°F (180 °C). Bake for a total of about 30 min.