Chop the rusks with a rolling pin or a soda bottle. (You can of course also put them in the food processor.) The consistency should be roughly the same as coarse breadcrumbs.
Mix in the eggs, broth, spices and butter. Shape the dough into small dumplings (approx. 30 dumplings for 12 rusks) and cook in the hot, not boiling broth. They are done when they go to the top.
First I form a test dumpling and add it to the broth. If it is too soft, simply add one or more rusks to the mixture.