Combine yeast, sugar, and 2/3 cup warm milk (not too hot or too cold) in a bowl and set aside till the yeast turns frothy or for about 10 minutes.
In a stand mixer bowl attached with a dough hook – add plain flour, salt, oil, egg, vinegar, and yeast mixture. Knead the mixture for about 5 to 10 minutes or until you get a smooth dough. You might require an extra 1/2 cup of plain flour. (you can also mix and knead the dough with your hands)
Transfer to a lightly greased bowl, cover, and set aside in a warm place until the dough doubles in size. (for 1 hour or less)
Preheat the oven to 250 degrees C.
Divide the dough into 4 parts and roll each part into a rectangle shape. Place the rolled rectangle sheets on a greased baking sheet.
Tightly roll the sides bringing them towards the center and forming a boat shape with the ends joined to each other.
Apply melted butter on the rolled sides with help of a brush or spoon.
Fill the boat-shaped rolled-out dough with the desired amount of both the cheese and top with tomatoes, olives, and mint leaves.
Finally, drizzle them with dried herbs and olive oil.
Place the baking tray in the center of the oven and bake for 10 to 15 minutes or till the cheese melts and the sides turn golden brown.
Serve hot.