Preheat oven (electric cooker: 200 °C/circulating air: 175 °C/gas: level 3). Wash potatoes thoroughly and cut them in half lengthwise. Place them in an ovenproof dish, with the cut surface facing upwards.
Season with salt and pepper. Bake in a hot oven for about 45 minutes. After 20 minutes sprinkle cheese on the potatoes.
Stir curd and mineral water until smooth. Season to taste with salt and pepper. Clean and wash spring onions and cut into thin rings. Stir into the quark.
Wash the meat, dab dry and cut into strips. Heat 1 tsp. oil in a frying pan. Fry the turkey strips in it all around for about 5 minutes. Season with salt and pepper. Arrange everything. The sweet potato can be eaten with skin on.