For the leek soup, wash the leek and cut into rings. Melt the butter in a saucepan and add the leeks – fry briefly.
Sprinkle the flour over it and pour in hot water. Add the soup cube and season with salt and pepper.
Let it boil for about 5-10 minutes, add the raw diced potatoes and let it finish boiling for another 30 minutes.
Finally, add some parsley to the leek soup.