For savory yeast dumplings, mix yeast, sugar, about 50 ml warm milk and 50 g flour to a dampfl (to a thick porridge). Cover and let rise in a warm place.
Once the dampfl has doubled in size, beat together with the remaining flour, the remaining warm milk, salt, egg and warm butter to form a dough. Let rise at warm room temperature for about 15 minutes.
Beat again and form about 10 dumplings from the dough. Place on a floured baking sheet, cover and let rise again in a warm place until doubled in size.
In a large pot, bring salted water to a boil. Put in dumplings and cook for about 20 minutes.
Lift out, arrange the savory yeast dumplings on warm plates and pour melted sasaka over them.