When my mother and I stepped off the musty, bare-bones bus that had lumbered neon-lit for six hours from the capital city of Guangzhou to Raoping, we could do nothing but nod passively to the suggestion of a late-night tea tasting at the home of our host Liu Jingjun. In this most northeasterly "town" of more than 1 million in China's Guangdong province, it is ...