As the craft beer scene becomes more and more obsessed with sours, make no mistake that some of the nation’s most thoughtful — if not outright intellectual — sours are being made locally at Beachwood’s Blendery in Long Beach.

After all, it would only be the experimental brain of Ryan Fields that cooks up a concoction like a sour coffee beer, and he’s done just that, partnering with next-door neighbor Recreational Coffee and its owner, the equally and wonderfully nerdy Bobby Hernandez, to create a coffee sour.

You read that right: a coffee sour, one of craft beer’s most rewarding and outright odd offerings. Dubbed Oaky Koke, named after the Ethiopian Koke roasted beans used to provide the coffee base, this definitively one-of-a-kind sour uses the acidity of coffee as a sweetening agent as opposed to using its roasting notes to play off malts.

“The Blendery’s beers are insanely nuanced,” Hernandez says. “So my proposal was simple: Let’s play with coffee and beer in a way that no one has. And as for the result, we’re just stoked.”

The product and partnership makes sense: Master brewer Fields plays with the idea of what a sour is and can be as much as he sticks to the long tradition that has made the beers of Cantillon, Rodenbach, Boon, and Dormaal worldwide legends.

“When Bobby started roasting, he called me to tell me he has this bean — this Ethiopian Koke — that has this almost umami-like profile,” Fields says. “And when I heard that, I realized that he was onto something I aim for: a fluid, wavelike flow of flavors and profiles. Most beers offer ‘hits’ of flavor: this is this, then that is that. What I try to create is the seamless blend of flavors and aromatics. I don’t want people to know where one part ends and the other begins.”

For beer geeks and coffee nerds alike, what makes Oaky Koke work is not just the mastery of Fields but the way in which Hernandez approaches the coffee itself. Most iced coffee revolves around cold brewing, that is, taking a large grip of ground coffee and setting it in a filter that sits in cold water for several hours. Recreational Coffee, which proudly alerts patrons that its iced coffee is not a cold brew, goes with the Japanese pour-over method: coffee patiently made by pouring hot water on beans, drip by drip.

The point? It creates astounding aromatics and activates the acids of the bean. And when flash-chilled over ice, it creates a wonderfully balanced drink, or an incredible additive for beer.

The drink is a nostril-full of coffee before a smooth and tart finish. It’s wonderfully challenging but not inaccessible, going fluidly through bitterness, fruitiness and tartness all in one taste.

“The first keg sold out extremely quickly, so we know we’re onto something,” Fields says. “Now that we have it more perfected, people are wanting to experience it more. … I am always looking for a more complex, balanced approach to making sours. We’re never going to beat anyone over the head with flavors. Just balance. And this beer is an expression of that.”

The Blendery will tap another keg of Oaky Koke on Thursday, March 9, at its location in Long Beach.

247 Long Beach Blvd., Long Beach. (562) 436-4020, beachwoodbbq.com./blendery.