Thinly slice the beef and onion.
Cut green onion, carrot, and shiitake mushrooms into bite-sized pieces.
Prepare the sauce (soy sauce, sugar, minced garlic, sesame oil, pepper) and mix it with the beef.
In an earthenware pot, layer onion, beef, carrot, and shiitake mushrooms in order.
Pour in enough water to just cover the ingredients and bring to a boil.
Once the soup starts boiling, add green onion and glass noodles, and simmer a bit longer.
Optional: Top with egg strips before serving for garnish.