How to make
Knead a soft dough from the ingredients for the dough. They need to be at room temperature and the milk needs to be slightly warmed.
Leave the dough in a warm area to double in volume. Divide the risen dough into 8 equal parts, shape them into balls, smear them with a little oil (so they don't catch a crust) and leave to rest for 15 min.
Smear your work surface with a little oil. Roll out each ball separately with a rolling pin, while making sure you smear each one with butter and sprinkle evenly with crumbled feta cheese.
Wrap them into rolls and arrange them in a spiral in an oven dish you've buttered beforehand, starting from the middle and going outward toward the walls.
Leave the prepared phyllo pastry to rise in volume for about 30 min., smear it with the egg yolk that you've beaten with 1 tbsp oil beforehand. Distribute the diced butter on top and bake in a preheated 300°F (150 °C) oven for 10 min. until it swells. Then turn up the heat to 360°F (180 °C) and bake finished to a nice crisp.