# Wash the
spinach, drain and chop it finely.
# Add finely chopped
onion and 4 tbsp vegetable oil on it, cover the lid on and cook it over low heat for about 20 minutes without water addition.
# When cooking the filling, cut the yufkas into 2 pieces at first, and cut them into slits which have the thickness of the large side of the matchbox.
# Put some cooled
spinach onto the narrow side of the triangles and put 1 pinch grated feta
cheese on it. Fold it from the edge as a triangle and then keep on rolling the triangle to cover the filling with yufka totally and then wet the end to stick it.
# You can add the remaining circular pieces of the yufkas onto the filling after cutting them into small pieces.
# Put the prepared boreks into hot oil and fry both sides. Serve them hot or warm.