Describe the Whipped Tea era.

The Whipped Tea era followed, as part of the Sung dynasty. Tea leaves in this era were ground to powder, and this powder was whisked in to hot water to create tea. Tea became quite a craze during this period, with tournaments held to find the best tea recipe among other things. Emperor Huei Tsung lavished much wealth on the attainment of rare species of tea, and declared white tea to be the rarest and best.