First, put the beef liver and lard through a meat grinder together.
Cut the bread roll into cubes.
Cream the soft butter with a hand mixer and mix with egg, mascarpone, spices, herbs and the liver. Also incorporate the bread cubes into the meat mixture and season with salt, pepper and a pinch of freshly grated nutmeg. Cover the mixture and let it rest for a few hours.
Form not too big dumplings with moistened hands.
Place the liver dumplings in a shallow saucepan in lightly salted simmering water for about 8 minutes.