My wife received this signature cookie named 下剋上鮎 (Gekokujō-Ayu) from Gifu. The design is so irresistible that it struck an indelible impression.

下剋上 (Gekokujō) refers to the lower overthrowing the higher.
"Ayu" (鮎) is a type of sweetfish commonly found in Japanese rivers.

Hence, when the characters are combined together, this gives rise to a fun idea of a fish overpowering a heron!