The next morning, mix together to a shaggy dough 500g flour, 300g water, and biga. Cover and let rest for about 30 minutes.
Immediately then put 3g of yeast, 20-30g of lukewarm water and a spoonful of flour in a small bowl. Stir well, cover and set aside.
In 30 minutes. combine everything without salt and butter and knead a smooth and supple soft dough. Now add salt and 30g of melted butter and knead about 1-2min.
Put the dough in a bowl, cover and let it rise until doubled in volume. It takes about 30-40 minutes depending on the room temperature.
From the prepared dough, make balls about 1 inch diameter and dip each into the melted dough.
Put the baking paper in a round baking tray (I use a cheesecake form) and spread the crushed feta cheese.
Arrange the balls on top without pressing them together. Cover with a towel and let it rise again. I use the oven with only the lamp on.
The final rise takes about 50 minutes, but you are looking to double the volume.
In a small saucepan, melt the butter over low heat and add the flour. Stir occasionally and cook until a light brownish color is obtained. Pull out of heat and season to taste.
Once the dough has doubled, brush with a yolk diluted with a little milk, and pour carefully with the brownish butter and flour on top.
Bake at about 170C in a preheated oven for about 25 minutes.
Serve warm with powdered sugar if you like sweet and salty.
Enjoy your meal.