Soak the **kombu** in the **chicken stock** for at least **30 minutes** to extract flavor.⏱ 30 min
Gently heat the stock with kombu over **low heat** for **15 minutes** (do not boil), then remove the kombu.⏱ 15 min
Whisk together the **soy sauce**, **mirin**, **ginger**, and **sesame oil** in the bottom of two large serving bowls.
Bring the broth to a rolling boil, then reduce to a simmer and keep warm while you cook the noodles.
Boil the **ramen noodles** in a separate large pot of water according to package directions, usually **2 to 3 minutes**.⏱ 3 min
Drain the noodles thoroughly, shake off excess water, and divide between the two bowls containing the sauce base.
Pour the hot broth over the noodles, stirring gently to combine with the sauce base.
Arrange the **soft-boiled egg**, **chashu**, **nori**, and **scallions** on top of the soup and serve immediately.