I've seen it as Cusquena Malta. When I've seen it. I haven't come across it in Chicago. It is brewed in the schwarzbier style: a dark (brown to impenetrable) lager that's not bitter, not sweet, not fruity, roasted malt in taste and aroma, can have a touch of smoke. Personally, I think it's kind of a simple example of style ... pleasant, but a bit sweet.
If you can't find the Cusquena - actually, even if you can - try a few other schwarzbiers. Sprecher's Black Bavarian is somewhat local and one of the best. Easy to find at stores and at bars. Goose Island has made a nice schwarzbier in the past but I think it was only available at the brewpubs.
Rogue's Skullsplitter is another favorite of mine though it's not indicative of the style - too big, too bitter, too hoppy ... and the hops bring citrus. As every particle has an anti-particle, this could be considered the anti-schwarzbier. I imagine a tasting in which a Sprecher drinker gasps at the skullsplitter "your schwarz is bigger than mine." Or Kelis sings a paen to it (her schwarz, is better than yours), and lifts a fiver from your wallet when your eyes are elsewhere.
rien