Empty the bread cubes into a bowl, add the parsley, salt and pepper. Roast the onions and fold in. Let cool down a bit. Then add the eggs and knead everything well. Let rest for 10 minutes. Finally only add enough milk so that the mixture can still be shaped well and does not become mushy.
Then form dumplings and let them simmer in plenty of gently simmering salted water for about 15 minutes.
The raw formed dumplings can also be frozen well in advance.