Step 1

In large pot, boil bonito flakes in 4 cups water to make dashi (fish broth), and simmer 2 to 3 minutes; strain flakes. Add soy sauce, sake, mirin, and 1 tsp salt, then turn heat to low. In a small pan, boil water and rehydrate noodles, 4 minutes; strain and set aside.

Step 2

In a medium bowl, combine chicken, remaining 1⁄2 tsp salt, green onion, and ginger; form mixture into 1-tbsp balls and drop in dashi-soy broth. Add cabbage, naganegi onions, Kikuna leaves, tofu, mushrooms, and carrots, and cook until vegetables are tender and chicken balls are cooked through, 10 to 15 minutes. Add noodles, desired toppings, and serve.