Cut the beef into bite-sized pieces and soak the seaweed.
Add sesame oil to a pot and stir-fry the beef.
When the beef is cooked, add the soaked seaweed and stir-fry together.
Pour in water and bring to a boil.
Season to taste with soup soy sauce and salt.
Skim off any foam that forms while boiling.
It's done when the seaweed is tender.