MooncakeCredit: Lybil BER, Wikipedia

Mooncakes are Chinese pastries that are shared and eaten during the Chinese Mid-Autumn Festival (also known as the Mooncake or Lantern Festival). The Mid-Autumn Festival is the second most important of the year, in the Chinese culture, and takes place on the 15th day of the 8th lunar month. Mooncakes were said to have been used to overthrow the Mongol led government during the Mid-Autumn Festival in the 14th century, when rebels hid covert messages in the center of the mooncake, rallying the "common" people.  Due to the integral part mooncakes played during the momentous event, mooncakes remain popular to this day during the Mid-Autumn Festival. More information on the festival can be found in the article, Mid-Autumn Festival.

Mooncakes are typically round or square in shape.  The exterior is made of a thin layer of egg washed and baked dough imprinted with a manufacturer's design, an auspicious design, or indication of filling flavor . The traditional dense fillings for a mooncake are red bean or lotus paste with an optional salt duck egg yolk that represents the moon. Other fillings include green tea, yam, chestnut, and dates.  Filling flavors have kept up with modern times however, and flavors such as rum and raisin, oreo chocolate, pineapple, cheese, and ice cream can also now be found.  With cultural influence in other parts of the world, durian flavored and Halal mooncakes that meet Islamaic food guidelines, can be found in Singapore, Indonesia, and Malaysia.

Mooncake with Lotus paste and egg yolkCredit: avlxyz, Wikipedia

During the Mid-Autumn Festival, mooncakes are shared with friends and family, often times while discussing folklore and admiring the full moon.  They are also given as gifts. Mooncakes are consumed by the slice, usually accompanied with Chinese tea to aid in digestion. 

Mooncakes can be purchased during late summer from Chinese bakeries and have also been seen in big box stores, such as Costco, in heavily Chinese populated areas in the US. Mooncakes can be found all over the world, mainly where a Chinese population or influence exists.