Wash potatoes thoroughly and cook in boiling water for about 15 minutes. Drain, rinse and peel. Peel onions, dice 1 onion very finely. Dice 2 onions. Clean, clean and halve the mushrooms.
Cut the meat into strips. Coarsely grate the potatoes. Season well with salt, pepper and nutmeg. Add very finely diced onion.
Heat butter and 1 tablespoon of oil in two portions in a frying pan (26 cm Ø), add half of the potato mixture to each portion and press flat to form a Rösti. Bake at low to medium heat for 4-5 minutes on each side until golden brown.
(Slide the Rösti onto a lid and turn carefully.) Slide out of the pan and keep warm.
At the same time heat 2 tablespoons of oil in a second large pan, add the mushrooms and fry vigorously while turning. Season with salt and pepper and remove.
Add another 2 tablespoons of oil to the pan, heat up, add the meat and fry vigorously while turning. Add the remaining onions and fry briefly. Season with salt and pepper. Dust with flour, sweat while stirring and gradually add stock and cream.
Bring to the boil, add the mushrooms and simmer for about 2 minutes. Season to taste with salt and pepper. Keep warm.
Clean and wash the salad, pluck into bite-sized pieces and drain well. Mix yoghurt, lemon juice, 1 pinch of salt and sugar. Mix salad and dressing. Wash parsley, shake dry and chop finely.
Pluck the hash browns. Arrange the shredded and rösti sprinkled with parsley on plates. Serve salad in small bowls.