For the filling, crumble the cheese, chop the parsley and mix both. For the dough, dissolve the yeast with the sugar in lukewarm water. Put the flour in a bowl, add the dissolved yeast, 2 egg whites and 1 egg yolk, oil, milk and salt and knead well. Cover with a clean cloth and let rise in a warm place for at least 1 hour. When the dough has risen, divide it into balls (slightly larger than a walnut), press the balls flat and fill with a well heaped teaspoon of the cheese mixture and seal. Brush with egg yolk and sprinkle with sesame seeds. Bake at 190 ° C (top / bottom heat) on the middle rack for 20 - 25 minutes until golden yellow. So far, these poaca have delighted everyone who has tried them. They are really very fluffy and taste very good!