If you grow up mostly in Tokyo like I did, there are so many regional Japanese dishes you only encounter only after you become an adult. One of my favorite of these late discoveries is from Yamagata Prefecture: a curiously named fresh vegetable relish called dashi.
Throughout most of Japan, “dashi” is the word for soup stock, the umami-rich broth that is the basis for so many savory dishes. In Yamagata, “dashi” also means this dish of finely chopped summer vegetables and herbs. There are various theories as to how the Yamagata dish came to be named this way — one holds that, just like dashi stock, the relish enhances the flavors of whatever it’s served with. Another theory is that the vegetables are kiridasu — “kiri” for cut up and “dasu” corresponding to dashi. Yet another explanation goes that it’s easy to very quickly make and serve (another meaning of “dasu”).
This, at least, is for sure: Almost every household in Yamagata has their own dashi recipe. The standard elements are fresh cucumber and eggplant since the dish most likely got its start as a way for farmers to consume excess vegetables quickly. Soy sauce, mentsuyu (soy sauce with dashi stock added), as well as aromatic summertime vegetables and herbs such as shiso (perilla) leaves, myōga (ginger) buds and ginger root also feature here. A type of green chili pepper called ao-nanban is often used in Yamagata, but any green chili pepper will do the trick if you can’t get your hands on this regional specialty.