Prepare the broth: In a large pot, combine chicken or pork broth, dashi stock, soy sauce, mirin, sake, sugar, garlic, and ginger. Simmer on low heat for 1.5 hours.

Cook the eggs: Boil eggs for 6-7 minutes for a soft boil. Immediately transfer to ice water, peel, and marinate in soy sauce and mirin mixture for 30 minutes.

Prepare the chashu pork: If using homemade chashu, slice it thinly after braising. Reheat slightly before serving.

Blanch the bean sprouts: Quickly boil bean sprouts for 1 minute, then drain and set aside.

Cook the noodles: Boil fresh ramen noodles according to package instructions (usually 1-2 minutes). Drain and rinse under cold water to stop cooking.

Assemble the ramen: Divide noodles among bowls. Pour hot broth over noodles. Arrange chashu pork, halved soft-boiled eggs, bean sprouts, and green onions on top. Add nori sheet on the side. Drizzle with sesame oil.