In the meantime, peel the onion and cut into cubes. Heat the oil in a pan and fry the onion with the diced ham. Then deglaze with the buttermilk and add half a cup of whole milk 1.5%. Now stir the spelled flour in cold water until smooth, add to the soup and briefly bring to the boil. Now season the soup with a strong pinch of nutmeg, salt and pepper from the mill.
Peel and slice the jacket potatoes and add to the soup.
The soup tastes best when it has been steeped overnight and is mashed with a magic wand after it has been warmed up.
We garnish the soup with a few oregano leaves before serving.