Boil potatoes until tender, mash smooth, and let cool slightly.
Mix in egg and salt, then fold in flour until you have a soft, non-sticky dough.
Divide into thirds, roll each into ropes, and cut into small diagonal dumplings.
Boil in salted water until they float.
Cook bacon in a skillet until crisp; remove.
Sauté mushrooms and onion in the bacon fat until golden.
Add peas to warm through, then butter to make a glossy sauce.
Fold in the dumplings, let them take on a little color, then add the bacon back in. Season and finish with farmer's cheese, fresh dill or parsley.
