Wash the potatoes and cook in boiling water for 20-25 minutes. Peel and chop the onions. Heat the oil in a pan and sauté half the onions in it. Add ground pork and fry for 3-4 minutes.
Wash the marjoram, dab dry, put some aside for garnishing, chop the rest finely. Add to the mince and fry briefly, season with pepper. Grate cheese finely. Put flour into a pot, add milk bit by bit while stirring and bring to the boil.
Add remaining onion and simmer at low heat for about 5 minutes. Stir in cheese, remove from heat, let cool down briefly. Mix eggs and sour cream, add and stir everything until smooth. Season with salt, pepper and nutmeg.
Drain the potatoes, rinse and peel them. Cut potatoes into thick slices. Put 3/4 of the potatoes into a greased, deep casserole dish or roaster. Spread the minced meat on top, add the rest of the potatoes.
Pour gravy over it. Bake in the preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: level 3) for approx. 30 minutes. Garnish with marjoram set aside.