電光石火
den.kou.se-.kka

Literally: lightning – light – stone – fire

Alternately: As quick as lightning or sparks struck from a stone. Doing something with incredible speed, or something happening in an extremely short span of time.

Notes: Apparently some people replace 石火 with a homophone such as 石下, but this is an error.

This compound is attributed to a 13th-century history of zen Buddhism in China known as the 五灯会元.

Also the name of a Hiroshima okonomiyaki restaurant chain, where presumably they take “fast food” to the next level. That dustpan-looking shape on the left is actually a spatula.