Q: What's hot and bitter with sugar on top?

A: Yerba mate, a caffeinated herbal drink popular in South America.

We were interested in trying mate, but had heard that the ritual aspects of preparing and serving the hot beverage are such that you can't really walk into a cafe and get it - kind of like a Japanese tea ceremony, I guess. But, on our last day in Buenos Aires, we stumbled upon a mate cafe run by a warm woman named Terese who was very happy to share the tradition with us.

Basically, you have a thermos of hot water and a cup - traditionally made from a gourd - packed with herb. You put sugar on top, add the hot water - no stirring! - and drink it through a special straw, made of silver or some other durable substance. For the first cup, you pass the cup around to the whole group, and everyone takes a sip, gaging your intake to so the cup is emptied by the last person. Then you refill the cup with more hot water, and start going around again, this time with each person drinking a full cup before adding more hot water and passing it along.

How does it taste? Well, I think these pictures speak for themselves.

Also? It's seriously freakin' caffeinated. Puts an espresso to shame. I think we finally figured out how the Argentines survive with no damn sleep.