Bonito flakes

Not vegan. If you see it, put it back.

Also spotted as

鰹節katsuobushi

the same, in kanji

かつお / 鰹katsuo

bonito (a fish)

削り節kezuribushi

shaved fish flakes

おかかokaka

bonito flakes with soy sauce

Where it hides

Okaka onigiri, めんつゆ (noodle sauce), ponzu, だし醤油 (dashi soy sauce), the topping on okonomiyaki and cold tofu.