Prepare the filling by adding the mayonnaise and yoghurt to the crumbled feta cheese. Sprinkle on the baking powder and stir the mixture well.
Lay out the phyllo pastry sheets on the table. Smear each sheet with an oiled brush. Fold in 2 and spread on the filling.
Fold by bringing the 2 ends of the wide side together and then fold the ends of the narrow sides to form rectangular phyllo pastries. Put the pastries in an oiled plate. Once you've prepared them all, fry in a greased pancake pan.
Flip them over to fry on all sides. Once they're ready, take them out onto a napkin and leave to drain the excess oil. Serve with yoghurt or ayran.