Image of Mid-Autumn Festival mooncakes from: Wallpaperz; check out http://learning.chinese.cn/en/article/2009-08/23/content_199948.htm for a cute video in Chinese with English subtitles explaining what the holiday is all about.
Autumn cake or Mooncake (simplified Vietnamese - Bánh trung thu ) is a Vietnamese bakery product traditionally eaten during the Mid-Autumn Festival (Trung thu). The festival is for lunar worship and moon watching, when mooncakes are regarded as an indispensable delicacy. Mooncakes are offered between friends or on family gatherings while celebrating the festival. The Mid-Autumn Festival is one of the four most important Vietnamese festivals.