# Put the
sugar cubes into half cup warm water at first, make them dissolve by stirring, then add yeast powder in it. Cover the cup and rest it for 10 minutes.
# Pour this mixture into a deep bowl, add egg white, salt and
olive oil in it.
# Add
flour into the mixture little by little, while kneading it. It must get a soft-medium consistency.
# Cover the dough and rest it for 45 minutes.
# At the end of the resting time, reverse the dough and knead it for a while more. Pick
walnut sized pieces from the dough, roll them over the bench into bars with pencil size.
# Get the ends of the bars together as circle. Place them onto the baking tray, which is greased with some oil, with spaces between them.
# After preparing all of the cookies, spread yolk all over them, sprinkle nigella seeds also. Rest them over the tray for 10 more minutes also.
# Place the tray into the oven, which is preheated to 374 F, and bake them until their surface turns to red.
