We could sum this one up lickety-split and be done with it - toss a yerba mate "tea" bag into a cup and add hot water. Done!
But if you really want to enjoy your yerba mate to the fullest you should try drinking it in the traditional manner, with loose leaf steeped in a gourd (mate) and sipped through a filtered straw (bombilla).
This is a time-honored ritual in South America, where yerba mate hails from. While it's not quite rocket science, there is an optimum way of going about things in order to get the best results. Tea Guy's hardly an expert on the topic, so I'll point you in the direction of some people who are.
How to Make a Great Cup of Unsmoked Yerba Mate, from the EcoTeas' Web site, is a pretty basic look at yerba mate preparation, as is Mate for Life's Preparing Yerba Mate.
For a slightly more involved look at how to go about things head over to the Natural Latitudes site and check out The Art of a Perfect Mate.
The Traditional Method, from the Ma-Tea.com site, presents both simple and more detailed explanations of yerba mate preparation and even throws in some helpful visual aids.
Over at My Mate World they've put together a similar explanation - How To Brew Yerba Mate - in the form of a nine-part slide show. This one is helpful for novice users who are having trouble visualizing one or more of the steps.
Yerba Mate Information, at The Yerba Mate Tea Gourd site, offers up links to a number of good informational resources, plus recipes and several helpful explanations on curing your mate and preparing the drink in various "styles".
For an intricate and detailed description of how to to prepare and drink yerba mate, plus some assorted and sundry facts, check out the Yerba Mate entry at Wikipedia.
Of course, if you don't have a bombilla, a mate or anything to put in the latter all this information is worthless. Fortunately all of the sites listed here - except Wikipedia - have a wide selection of all of the above. Enjoy.
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tea, food, food and drink, yerba mate