Remove the skin from the onion and cut into fine rings. Rinse the leek and cut it into fine rings as well.
Heat the oil in a saucepan and sauté the onion and leek rings in the fat. Add the minced meat and sauté. Season everything with salt and pepper and cook for 5 minutes with the lid closed. Add the wine and water and bring to a boil. Add the processed cheese and let it melt. Bring the soup to the table hot and sprinkle with the chopped parsley.