You may be talking about the fruit of Quercus crassipes, also known as Anemone, Yishen and Tianzhu, which are named after their fruit shapes, cooked or used for wine making. Produced in southern Fujian, Hunan and Guizhou provinces, as well as Taiwan Province, Guangdong, Guangxi, Yunnan and Hainan. It is also distributed in northeastern Vietnam.