While we were vacationing in China I kept seeing these rolled egg cookies for sale in the stores that were selling souvenir type foods, especially while in Shanghai. Amongst the bags of sugared fruits and peking duck were red boxes with a photo of these cookies on the front. Compared to the other stores where we could grab a snack, the souvenir food was expensive so we gave the cookies a pass.
I had pretty much forgot about them until we were visiting a wet seafood market in a fishing village on the edge of Hong Kong. I had expected the market to smell like fish, but because the fish were kept alive in tanks there was almost no seafood scent. Instead, the entire market smelled like... cookies. The way ice cream parlours smell when they make their own cones : butter and vanilla sizzling on a hot iron.