Sift the flour in a bowl, make a well in the middle of it, put all the remaining ingredients for the dough in it. The butter needs to be melted but not hot. Add the activated yeast and butter slowly, gradually kneading.
You need to obtain a soft and very smooth dough. If needed, add a little more flour to prevent sticking. Cover with a towel and leave in warm area to rise. It needs to double in volume. What I do is I turn the oven on to 104°F (40 °C) with the fan on - the dough is ready in about 20 min.
After the dough has doubled in volume, move it to the counter, knead briefly, divide into 6 equal parts. Roll out each part into a long, narrow rectangle.
Smear it with melted butter, sprinkle feta cheese and wrap into a tight roll, starting from the lower end. Cut the prepared roll into 2 parts lengthwise. Wrap each part into a spiral and put in a muffin tray that you've smeared with butter ahead of time.
Repeat this process with every part of the dough.
Return to the oven to rise again - about 15 min.
Bake in a preheated 356°F (180 °C) oven about 25 min.
And while you're impatiently waiting for them to cool, prepare ingredients for another batch because they'll be gone before you know it - they're so tender and soft.