Wash the potatoes, drain and quarter them. Wash the meat, dab dry and cut into pieces. Heat oil in a pan and fry the meat in it for 2-3 minutes on each side.
Season with salt and pepper. Remove from the pan and set aside. Add the potatoes to the frying fat and fry all around for about 15 minutes at medium heat until golden brown. In the meantime peel and roughly dice the onion.
Clean, wash and cut the peppers into pieces. Add the onions and peppers to the potatoes 5 minutes before the end of the frying time and fry with them. Season with salt, pepper and chilli powder. Add the meat to the potatoes shortly before the end of the cooking time and mix in.
Season sour cream with salt, pepper and chilli powder and spread it over the potato pan. Grate the cheese finely and sprinkle over it. Bake in the preheated oven (electric cooker: 200 °C/ gas: level 3) for 10-15 minutes.
Clean and wash spring onions and cut into fine rings. Sprinkle over the potato pan and serve garnished with parsley if desired.