Tokyo's classic soy-sauce ramen - a clear, translucent amber chicken-and-dashi broth kept apart from a separately concentrated soy sauce tare, the two combined only at the very last step in each bowl so every serving's seasoning stays precise.
1.Combine the water and the larger piece of kombu in a pot and let sit at least 30 minutes, then heat gently just until small bubbles form around the edges - never let kombu boil, which turns dashi bitter and slimy.
2.Remove the kombu, add the cup of bonito flakes, turn off the heat, and let steep 5 minutes, then strain - this is your dashi base.
3.In the same pot, combine the strained dashi with the chicken thighs, scallion pieces, ginger, and garlic, and simmer gently, uncovered, for 45-60 minutes, skimming any foam, until the broth is savory and the chicken is cooked through - keep it at a gentle simmer, not a rolling boil, so the broth stays clear and amber rather than cloudy, which is what separates shoyu ramen from tonkotsu.
4.Remove the chicken, let it cool slightly, then slice it for topping the bowls; strain the broth and keep it hot.
5.Make the tare separately: combine the soy sauce, mirin, sake, the small piece of kombu, and the tablespoon of bonito flakes in a small saucepan and simmer gently for about 5 minutes to concentrate the flavor, then strain - keeping the tare and the broth as two separate components, combined only in the bowl, is what lets you control the seasoning intensity of every serving precisely.
6.Soft-boil the eggs (6.5-7 minutes in simmering water, then into an ice bath), peel, and let them sit in a splash of the finished tare for at least 30 minutes to pick up color and flavor, then halve.
7.Cook the ramen noodles in a separate pot of boiling water according to the package directions, just until al dente, then drain well - never cook noodles in the broth itself, which would cloud it and dilute the seasoning.
8.To assemble, spoon 2-3 tablespoons of tare into the bottom of each bowl, ladle in the hot broth and stir to combine, add the drained noodles, then top with the sliced chicken, a halved marinated egg, sliced scallion, menma, and a strip of nori.