The secret to Germknödel's fluffy texture is proper kneading of the yeast dough and sufficient rising time. It is best to steam the dumplings rather than boil them in water, to keep their shape and prevent them from becoming soggy.
When filling, ensure the edges of the dough are tightly sealed to prevent the jam from leaking out during steaming.
Prepare the starter: add crumbled yeast and 1 tsp of sugar/flour to lukewarm milk (200 ml). Let it activate for 10 minutes.
In a large bowl, mix flour, remaining sugar, egg yolk, melted butter, and salt. Pour in the starter and knead a smooth, non-sticky dough.
Cover the dough with a tea towel and let it rise in a warm place for 60–90 minutes until it doubles in volume.
Divide the risen dough into 4 equal pieces (or 6 smaller ones).
Flatten each piece into a disk. Place 1-2 tsp of plum jam (Powidl) in the centre.
Carefully seal the edges of the dough to form a neat ball with no visible seam. Place them seam-down on a floured surface and let them rise again briefly for 15 minutes.
Bring water to a boil in a large pot. Place a steamer basket or cloth over the pot, ensuring the dumplings do not touch the water.
Carefully transfer the dumplings to the steamer (leave space between them, as they will expand) and cover with a lid.
Steam for 12–15 minutes. The dumplings should be fluffy and elastic. Do not lift the lid during steaming!
Tip: To prevent the dumplings from collapsing, pierce them immediately with a toothpick after steaming.
In the meantime, mix the ground poppy seeds with powdered sugar. Melt the butter for drizzling.
Place the cooked Germknödel on a plate.
Drizzle each dumpling generously with melted butter and heavily dust with the poppy seed-sugar mixture.
Serve immediately, warm.