New Belgium Brewery, Allagash Brewing Craft Vrienden

When it comes to beer, the adage that two heads are better than one is gaining newfound traction.

Since 2009's Life and Limb–a breakthrough collaborative effort of beer bigwigs Sierra Nevada and Dogfish Head–the floodgates have opened, with more breweries forming partnerships to create special releases together. Lucky for drinkers, these group efforts are proving to be some of the most interesting suds on the shelves.

Our favorite of late, called Vrienden, has a Flemish accent. Begat by New Belgium Brewery in Colorado and Allagash Brewing Co. in Maine (both domestic operations with a Belgian bent), the brew is not for a conservative palate. The first batch, nicknamed Vrienden West because it's produced at the New Belgium facility, is an odd blend of hibiscus, butter-braised endive (yes, the same bitter green you find in salad) and Allagash's wild yeast for its makeup.

We half expected a car wreck of overpowering flavors in the glass, but Vrienden West's mishmash is surprisingly successful: The copper-colored pour is slightly sour, with strong cherry notes that segue into a dry herbaceousness.

But don't wait; Vrienden West is only available for a few more weeks. In February, a slightly different recipe called Vrienden East, brewed in Allagash's facility with elderberry and dandelion greens, will replace it.