Cut the ugeoji into bite-sized pieces and wash it thoroughly, then set it aside in a bowl.
Trim the green onion and cut it into bite-sized pieces as well.
Mix all the sauce ingredients together ahead of time to make the seasoning sauce.
In a pot, add 200ml of water, the beef, and a pinch of salt, then stir-fry over high heat.
Once the beef is no longer pink and the water starts to boil, add the ugeoji and stir-fry together for another 2–3 minutes.
Add 1L of water along with the seasoning sauce you made earlier, and simmer for 10 minutes.
Add the beef bone broth and green onion, then simmer for another 5 minutes and it's done.
Tip.Stir-frying the ugeoji with the beef first helps the seasoning soak in more deeply for a richer flavor. Adding the beef bone broth at the end gives the soup a deeper, more robust taste.