Dissolve the yeast in lukewarm water and process with the flour into a yeast piece. Let rise in a warm place for about 1 hour.
Mix the potatoes with the butter, sugar, eggs and salt. Then mix well with the yeast piece.
Roll out the dough as thick as a thumb on a greased tray, prick, brush with melted butter, sprinkle with cinnamon and sugar and drizzle with melted butter again.
Bake in the oven at 180 ° C top / bottom heat for about half an hour.