Daikon (radish) pickled in koji. べったら漬.
A type of tsukemono (pickled or preserved vegetables) popular in Tokyo. It can be rather sticky or "bettara" due to the amazake on the surface and that is how it got its name. The taste is crisp and sweet, and it has an alcoholic aroma.
[Betterazuke]
The main difference with takuan, another pickle made from daikon (with the nukazuke method) is that the radishes used for bettarazuke are not dried. Therefore the liquid content of the pickle may be as high as 80%. It does not keep very well and should be consumed soon after opening.
Bettarazuke stems from the Edo period, when at the Takarada Ebisu shrine in Nihonbashi Honcho a "Bettera Fair" (Bettera Ichi) was held on the night of October 19 - a custom which still continues.
Photo own work.
Japanese Food Dictionary