For the potato-mushroom soup, melt the butter in a pan and brown the onion a little, add flour and marjoram and fry briefly.
Pour in soup or water, stir in brunch and add potatoes.
Simmer slowly for about 30 minutes and season with salt and pepper.
Carefully place the raw ham on a baking paper and bake in the oven at 180° C for about 10 minutes. Take them out, let them cool down and remove them from the baking tray when they are cold.
Then serve the raw ham chips in the hot potato-mushroom soup.