Wash the potatoes in their skins, then cut them into rounds of about 1 cm, they should not be too thin because they dry out, then season them and put them in the oven in a tray lined with baking paper, about 1 hour until baked .
Meanwhile, cut the kaiser into small cubes and heat them a little in oil.
Grate the cheese and chop the onion.
After the potatoes are cooked, take out the tray and put kaiser, cheese and green onions on each round and put them in the oven for another 10 minutes.
They can be served as a side dish or simply plain with a salad or as alexj says with sour cream.