How to make
Make a roux from the oil and flour and dilute it with 6 cups of water. Once it comes to a boil, add the finely diced zucchini and salt to taste.
Once the zucchini soften, add the finely crumbed feta cheese. Immediately remove the soup from the stove and thicken it with the beaten egg and yoghurt. Sprinkle with black pepper and chopped dill.