The collaboration between Atlas, The Radler and Baderbrau produced the limited-edition and aptly named Tricycle.
The brew became available last week at both Atlas, 2747 N. Lincoln Ave., and The Radler, 2375 N. Milwaukee Ave.
Tricycle is an Altbier, a style that originated in Germany, and has a smoked malt, which makes it stand out from the typical Altbier, according to the brewery.
While the Saller brothers, who run Atlas, don't typically brew German beers, they recently learned their great-great-great-grandfather was an immigrant from Germany who founded the first major brewery in Kansas City.
"I thought that was pretty cool," Ben Saller said. "It's made me explore my German heritage as it's related to beer a little more."
Saller had been talking for a while about collaborating with Bob Sama, a Chicago brewer who recently resurrected the 1980s-craft beer Baderbrau, and when The Radler also indicated interest in joining forces, it was a no-brainer.
"The Radler sounded like the most awesome place ever to me," Saller said. "I said, 'Hey, I'm not trying to usurp your house beers, but as a one-off would you want to brew together?'"
The process included throwing a bunch of ideas around, and using a base recipe from Atlas Brewing.
Sama had some suggestions, including featuring German and Czech hops, to add some of the Baderbrau characteristics.
"It's a great example of the kind of fun and I hope interesting types of things that can happen with beer and food in Chicago right now," Saller said. "I don't think that was true a few years ago."