Combine minced pork, light soy sauce, sake, mirin, sesame oil and water together. Set aside.
In a small pot, add in the stock, cover and bring to a rolling boil. Add in kimchi, cover and bring to a boil.
Remove the pot cover, give the minced pork a stir and add them into the the pot. Stir with a spoon to break up the minced pork. Cover, turn down the heat and simmer for 2 minutes. If you want bigger meatballs, add the minced pork in by spoonfuls, cover and simmer for 2 minutes then give the mixture a stir.
Taste the soup at this point - if it's not salty, season with salt. If it's too spicy, add in a little sugar to offset the spiciness.
Add in the egg noodles and cook until the egg noodles are done (like how you would cook an instant noodle). Turn up the heat, add in the beaten egg and leave it untouched for 15 seconds. Give it a quick stir, remove from heat, garnish with chopped spring onions and serve immediately.
NOTES
- If you like soft-boiled eggs instead of scrambled eggs, add in the egg when you add in the egg noodles. By the time the egg noodles are ready, the egg should be ready too with a soft yolk center.