If the rolls are soft, slice them, place them on a baking sheet, and put them in the oven at 350 degrees F until dry. Cut the rolls into 1/4-inch cubes. Pour the milk over the bread and soak.
In the meantime, melt the butter in a skillet. Sauté the onion until translucent. Add the parsley and cook for 1 more minute.
Squeeze any excess liquid from the bread and mix the bread with the onion. Lightly beat the eggs and incorporate them into the paste.
Wash the liver and pat it dry with paper towels. Chop it very finely with a sharp knife or grind it in a meat grinder and add it to the mixture. Add the marjoram and lemon zest and season generously with salt and pepper.
Bring a large pot of salted water to a boil. Reduce the heat to a simmer. Shape a tiny test dumpling and drop it into the water to check for the right consistency. If the dumpling falls apart, add bread crumbs, a teaspoon at a time, and test again.
Shape 8 large round dumplings and lower them into the simmering water. Cook covered for 25 minutes without boiling.
In the meantime, heat the beef broth thoroughly. Remove the dumplings from the water with a slotted spoon, drain, and place them in individual soup plates or a large soup bowl. Ladle hot beef broth over them, garnish with chives, and serve very hot.