In a country where tea names can lean toward the poetic ("iron goddess of mercy," "longevity eyebrow"), kuding tea is impressively straightforward: literally "bitter nail tea," describing not just the flavor, but the needle-like shape of its twisted dried leaves. As with many other herbal medicines, drinkers in Guangxi and An Hui provinces (and elsewhere) ascribe a wide, wide range of curative powers to this holly plant, a relative of the New World drinks yerba mate, guayusa, and yaupon. Kuding tea, which is slightly caffeinated, can—purportedly—improve circulation, help you lose weight, regulate temperature in the body, and, of course, cure the common cold. I'm skeptical of all these claims, but there's no arguing that the tea's rich texture and profound bitterness have the power to soothe the throat like nothing else. Bitterness is an under-appreciated flavor in the Western canon, but it's an impressive physiological reset button. When you're slurping this stuff down, no stuffy cold can faze you.