Cut beef and radish into bite-sized pieces.
Slice green onion thinly.
Add sesame oil to a pot and stir-fry the beef.
When the beef is half cooked, add the radish and stir-fry together.
Pour water and bring to a boil.
Remove any foam from the surface.
Season with soy sauce for soup and salt.
Add green onion and boil briefly once more.