Wash the beef and dry it with a kitchen towel.
In the large pot pour around 1,5l water, turn the heat on (high), add salt and wait until it starts boiling.
Add beef topside, carrots, leek, parsley and celery root as well as peppercorns. And wait until it boils again. Turn the heat to medium-low.
Simmer for at least 2h or when the meat is tender.
In the meantime peel the potatoes, wash them and cook them in salty, boiling water for 20 minutes.
Take the piece of meat out of the broth and cut in very thin slices.
Serve with Frankfurt Green Sauce on the side.