A pu’er is a type of fermented tea produced in China’s Yunnan Province – where the style was invented. Whenever a fermented tea is produced outside of Yunnan Province — as ours are — it is called a “dark tea.” The process involves microbial fermentation of the tea leaves after they’ve been dried and rolled — which results in a variety of flavors, often earthier than other teas. Dark teas age like wine, often increasing in complexity over years. You’ll sometimes see them pressed into cakes or bricks.