I remember having been in Japan and ate several meals of cold soba. Their cold soba broth taste like soy sauce with only a stint of saltiness; it doesn't taste like it's made of sushi type sweetened ...
Just to be clear, I'm not asking for a recipe, just some ideas. Which ingredients will create a quick yet flavourful and umami full broth? I've got things like dashi and miso but even then it doesn't ...