Cover the potatoes and boil them in water for about 20 minutes. In the meantime peel and finely dice the onion. Cut bacon into fine cubes. Clean mushrooms, wash if necessary and cut into thin slices.
For the mushroom filling, heat 1 tablespoon of oil in a pan. Fry the mushrooms in it. Add half the onion and sauté briefly. Season with salt and pepper. Remove everything.
For the bacon filling, heat 1 tablespoon of oil in the frying fat. Fry the bacon in it for about 1 minute. Add pimento and remaining onion, fry until translucent, turning. Take out, let cool down.
Drain the potatoes, quench, peel and press them through a potato ricer while still hot. Immediately knead in 1 level teaspoon of salt, nutmeg and egg yolk. Let it cool down a little, then knead in 125 g flour.
If the potato mixture is too sticky, knead in the remaining flour. Then form the mixture into a roll with floured hands (dough sticks a little bit). Cut into 12 slices of the same size.
Place 1 slice of dough on each floured palm and press it flatter if necessary. Add 2 teaspoons of filling to each slice and form the potato dough into a dumpling. Process the remaining dough and the remaining fillings in the same way, filling 6 dumplings with bacon and 6 with mushrooms.
Cook the dumplings in plenty of boiling salt water for 20-25 minutes.
In the meantime, wash the herbs and shake them dry. Pluck off leaves and chop them roughly. Melt butter. Season with salt and pepper and stir in the herbs.
Lift the dumplings out of the water with a skimmer and allow to drain. Sprinkle with the herb butter. Add the cranberries. Serve with a salad of lettuce hearts.