Habutae mochi; smooth white mochi
A type of mochi named after its resemblance to habutae silk: smooth, white, and delicate. Often associated with Fukui Prefecture.
I had some Habutae mochi, a specialty of Fukui.
Habutae mochi has a fine texture and an elegant sweetness.
羽二重 is the silk fabric itself; 羽二重餅 is the confection named after it.
餅 is the general term for pounded rice cake; 羽二重餅 is a specific variety.
From 羽二重 (habutae, a type of smooth silk) + 餅 (mochi, pounded rice cake), referring to the confection's smooth, white appearance.