Put yeast and sugar in the warm milk, and let the yeast proof for few minutes.
In a bowl, whisk the egg, salt, olive oil and butter.
Add the yeast mixture.
Add the sifted flour gradually until obtain a nice soft dough.
Cover the dough in that bowl and let rest for about 1 to 2 hours until doubled in volume.
Dump the dough on a slightly floured working board.
Deflate with hands and roll into a log.
Cut into small equal pieces.
Form a ball with each piece.
Flatten each ball with your hand to form a circle.
Mix Feta cheese with chopped parsley.
Place about 1 tablespoon of Feta parsley mixture in the center.
Fold the dough over the filling.
Seal the dough with hands to cover the filling.
Turn the Pogaca formed with the seam side down.
Place the Pogacas in a baking sheet, lined with parchment paper.
let rest for about 20 minutes.
Brush with egg yolk mixed with milk.
Sprinkle sesame seeds or Nigella seeds on top.
Bake in a 350°F preheated oven for 20 to 25 minutes or until golden.