Clean and wash the spinach, drain well and chop roughly. Peel onions and garlic and chop very finely. Heat 2 tablespoons of butter in a frying pan. Fry the onions and garlic until translucent. Remove and let cool.
Coarsely grate the bread. Grate parmesan. Mix ricotta and eggs well. Add onions, garlic, bread, cheese and starch and stir well. Stir in spinach. Season with salt and pepper. Cover and let rest for about 30 minutes.
Form 8 dumplings out of the spinach-ricotta mixture with floured hands (stick something). In a large pot, boil up plenty of salted water. Add the dumplings and let them simmer at low heat for about 8 minutes until they rise.
In the meantime brown 5 tablespoons of butter in a small pot. Lift the dumplings very carefully out of the water with a ladle (they are very tender and soft) and let them drip off a little. Arrange two dumplings each with some browned butter.