Guayusa (pronounced gwhy-you-suh) is only starting to make inroads into the U.S., but it's hardly new. The flavor is similar to yerba mate, but with a more plush, fruity flavor and a complete lack of bitterness. Tasting invites comparison to green tea, but the flavor is less tannic and the texture is more creamy. Unlike green tea, drinking it on an empty stomach won't give you a stomach ache. And just as important, it's nearly impossible to overbrew, and leaves can be resteeped half a dozen times before their flavor starts to wane. Have you ever tried it?