The ramen component that seasons the broth is tare.
Tare is a concentrated seasoning sauce added to ramen stock, usually just before serving. Its main job is to supply salt, but it also contributes umami and distinctive flavor. Common styles include shio tare based on salt, shōyu tare based on soy sauce, and miso tare based on fermented soybean paste.
Tare is separate from the broth itself. The broth supplies much of the liquid, aroma, and body, while tare establishes the bowl’s seasoning level. This is why two ramen bowls made with similar chicken or pork stock can taste very different when their tare changes.
A common mix-up is confusing tare with dashi. Dashi is a stock or stock component, often made with kombu, dried fish, or mushrooms. Nori and menma are toppings: dried seaweed and fermented bamboo shoots, respectively. Tare can also be used outside ramen, including as a Japanese grilling or dipping sauce.