For yeast dumplings with poppy seeds, first pour flour into a large bowl. Warm the milk a little, stir with the crumbled yeast and sugar until smooth and pour over the flour.
Add salt, egg yolks and melted butter and mix until smooth. If necessary, add a little more milk and stir until the dough comes off the wooden spoon.
Then cover the dough with a crockery stick and let it rise in a warm place for 1 hour.
Stir the powidl well with the rum and cinnamon. Divide the risen dough into twelve equal pieces. Place 1 teaspoon of Powidl in the center of each piece pressed a little wide and form into dumplings. Place the dumplings on a floured board and let rise for about 25 minutes.
Cook in mildly salted water over low heat for about 6 minutes, then turn over and let stand for 6 minutes until done.
To serve, sprinkle yeast dumplings with enough poppy seeds and sugar and baste with brown butter.