Wash the potatoes unpeeled and wrap in aluminum foil. Place on a tray and bake at 200 ° C for 90 minutes.
Cut the spring onions into thin rings. Mix the sour cream, cream, cheese, diced ham and spring onion rings well in a bowl, cover and leave in the refrigerator until the potatoes are ready (at least 60 minutes).
Let the potatoes cool down briefly, take them out of the aluminum foil, cut them in half and place them back on the baking tray. The mass in the bowl has now become a little stiffer. Stir well again and then spread over the potatoes. Bake the potatoes again at 200 ° C for approx. 20 - 30 minutes until the desired degree of browning is achieved.