I first tasted it at the Shanghai Restaurant in Monterey Park and loved it. The winey rice grains and chew sesame tang yuan in a hot, sugary broth served on a cold weather was perfect. :)
TM from China taught me how to make it....
Basically, purchase a container of sweet rice ( it's sweet rice fermented with yeast). It is usually found in oriental markets like 99 Ranch Market in the tofu section. Place half a cup of the rice in a pot of water ( about 6 cups) with 5 inches of ginger. Add more rice if you like a stronger "wine" taste. Once it comes to a boil, beat in 2 eggs and switch off the fire.
In another pot, boil the tang yuan.
To serve, place the tang yuan in a bowl, and ladle the syrup over the rice balls. :)