Knead the mince with the finely chopped onions, spices and yoghurt (to make the mince juicier), leave it aside until it's time to use it.
Boil the potatoes in salted water, leave them to cool, peel and grate them on a grater. To them, add the egg, black pepper, salt and flour.
Knead a thick dough that sticks to your hands, put it on a well-floured counter, divide it into 9 equal parts. Roll out each one into a thin sheet, distribute stuffing evenly on top and wrap them into rolls.
Pour the oil in a large pan, place the rolls, fry on all sides until lightly browned.
Arrange the braised rolls in a tray and bake 15-20 min. in a preheated 392°F (200 °C) oven.