How to make
Sift the flour with the salt along with the baking soda. Pour the melted butter into it, make sure it's not hot. Add the yoghurt containing the ammonium bicarbonate and pour in 1 tbsp lemon juice on top to extinguish it. Stir to effervesce. Add 1 egg white, leave the yolk for smearing on top.
Knead a soft dough until all the flour's absorbed. Roll the dough out onto a lightly floured counter in a rectangular form, about 1/4 thick.
Cut the sheet into 3″ (7 cm) x 3″ (7 cm) squares.
For the filling, mash the feta cheese and add 2 eggs, beaten with a fork. Stir the mixture. Scoop from it with a spoon, distribute it over the cut out squares.
Roll them up into rolls. Arrange them onto baking paper in a large baking tray.
Turn the oven to heat up to 390°F (200 °C).
Smear the rolls with egg yolk and sprinkle with sesame seeds.
Bake the crackers for 15 min.
