# Put the
yogurt, granulated
sugar and the margarine, which is softened at room temperature, into a deep bowl. Whisk or blend the mixture, until the
sugar dissolves totally.
# Add vanilla and baking powder into the mixture. Add the sifted
flour little by little while kneading the dough.
# Cover the dough and rest it for 10 minutes. Meanwhile, prepare the stuffing; Pound the
walnut, mix it with sultana, cinnamon and granulated
sugar.
# Divide the rested dough into 4 equal pieces. Roll out the first piece of the dough into 1/4 inch thickness with square shape. Lay quarter of the prepared stuffing all over the rolled out dough piece and roll it.
# Repeat the same processes for the remaining 3 dough pieces. Lace the 4 rolls onto the lowest layer of the refrigerator to harden them, and refrigerate them there for half an hour.
# At the end of the resting time, cut the rolls into the circle shaped pieces, each has 1/2 inch thickness. Then place the pieces onto the greased baking tray with some spaces between them.
# Place the tray into the oven, which is preheated to 350 F. Bake the cookies, until they turn to light pink.
# Serve them cool.
