Boil or steam the potato, then mash it using a fork.
Heat the cream, then mix in salt, pepper and, nutmeg. Add the potato, and cook for a few minutes.
Add the diced butter, then finish with grated parmesan.
FOR THE BEEF SHANK
Season the beef with salt, pepper and flour, then cook briefly in a sauté pan using olive oil. Remove the beef and set aside.
Using the same pan, add carrots, onion, and celery. When the vegetables are soft, add the butter, salt, and pepper then cook for 5 minutes.
Add the beef shank, pour in the wine and let it reduce by half. Then add peeled tomato, bay leaves, pepper corn, and 1 cup water. Bring to a boil then reduce the heat to low. Cook for 2 hours until soft.
When the meat is cooked, remove the meat and keep aside. Remove the bay leaves from the sauce, then blend the sauce in a food processor. Add the gremolada. Serve with sauce and mash potato.