The first time I saw Zeph Shepard, he was dressed in a leather cap, denim overalls and flip-flops — “rainbow doublestuffs,” he later explained, not entirely helpfully. He was, at that precise moment, jogging across Southeast Foster Road to help an elderly neighbor remove a piece of plastic that had tangled up in his lawn mower blade.

What does that have to do with burgers? Well, before he fixed the mower, Shepard had been hosting — in his way — Butcher’s Burger, a monthly event at his Proletariat Butchery. There, on the last Friday of each month, Shepard and a small crew place a metal grill on the sidewalk, build a fire, crack cans of beer, pour glasses of wine and sell a short menu consisting of potato salad and one singular burger, no substitutions, save the option to add a slice of American cheese for $15 (more on that later).

The impromptu mower repair also offers insight into Shepard’s philosophy — no small thing considering that, during a follow-up phone conversation, he asked me whether I had heard of both Plato (and his ideal forms) and Aristotle (and his first principles). Shepard started making food as a kid, after finding that strawberry ice cream from the store didn’t have enough strawberries. He taught himself about meat after deciding to throw a pig roast for some friends. He’s not afraid to try new things, or get his hands dirty. And if he’s going to make a burger, he’s going to do it his way.

The Butcher’s Burger — its fresh-ground beef seared on a wood-fired grill, basted in flaming beef tallow shot from the bottom of a medieval French tool called a flambadou, then placed inside a squishy bun with house mayo and pickles — might be the best burger I have ever had. Or maybe it’s just my favorite right now. Or perhaps I can’t stop thinking about it because it’s only available once a month, an increasingly common phenomenon in Portland’s rarified burger universe.

Either way, the burger is fantastic, with juicy beef seasoned with salt, pepper, fresh oregano and garlic; an epic crust that correctly suggests the meat has been deep fried in beef fat; and a profound tang coming from that one-two punch of pickles and mayo. You want a Maillard reaction? This burger gets sent through the umami version of a Large Hadron Collider. Even the bread (most recently a potato bun from Gabriel’s Bakery) does its job, holding everything in place without getting in the way.

Call it the anti-smash burger.

As you might expect from a butcher, Shepard’s ideal burger is a showcase for beef. In this case, back leg meat from an Anderson Ranch cow, a hard-working muscle with a dark red color and rich beefy flavor. During Butcher’s Burger, he asks his team to grind and season the beef every hour, on the hour, both to ensure freshness and to offer a peek behind the apron for customers waiting in line.

Once formed, each patty is seared on a griddle placed above the coals. After they’re flipped, lead cook Luca Ponti takes a chunk of house rendered and seasoned beef fat, a product Shepard hopes to brand as “Butcher’s Butter,” and plops it in a red-hot flambadou, a metal tool with a hollow cone at the end of a long handle that Shepard prefers to call a “tack.” Once aflame, Ponti dabs each burger with the cone, dripping seasoned finishing fat onto the sizzling beef.

It’s an old fashioned way to build up the Maillard reaction, the process that gives browned foods their appetizing aroma and flavor (and lets our lizard brains know the meat is safe to eat). And it achieves that result without smashing the meat into a thin, crispy beef chip, a trendy technique that Shepard thinks takes the Maillard obsession to its “idiotic logical conclusion.”

And that brings us to the cheese.

“If a friend asked me to go get a smash burger, I would say, ‘Yeah, sure.’ But professionally, I know it’s (hogwash),” Shepard says, using a stronger term. “The whole point of putting a piece of American cheese on a smash burger is you’ve cooked the burger improperly. You’re not getting juicy beef. And then you need this industrial cheese to replace the fat that you’ve errantly cooked out of it.”

So, at the next Butcher’s Burger event this Friday, June 28, Shepard plans to offer Boar’s Head American cheese for $15 a slice.

Save your money. The Butcher’s Burger is plenty juicy without the cheese, and at $12, priced fairly reasonably compared to the upscale $20 burgers currently hitting the market.

Shepard is mostly self-taught, though he previously worked at Pastaworks, took an apprenticeship with Sea Breeze Farm on Vashon Island in Washington (and now operating a Northwest Portland restaurant and charcuterie truck), and another with famed Italian butcher Dario Cecchini. Just before the pandemic, he briefly started a salumeria on Northeast Fremont Street, then moved to this graffiti-soaked stretch of Southeast Foster, reopening last year. Instead of a butcher’s case, Proletariat Butchery sells meat in shares, offering classes and wine tasting events from Shepard’s wife, former Olympia Provisions sommelier Emily Salko.

Butcher’s Burger actually started as a pickup party for Proletariat’s nascent sausage club, but it soon took on a life of its own. For the first event, Shepard and his team cooked 75 burgers. By May, they made 360. On Friday, they will prepare 425. It might not be enough.

Shepard has no desire to make burgers more often.

“I’m a butcher,” he says. “I never want to run a burger shop. But if I can do something cool once a month, and do it really well, then that’s what I’m going to do.”

If you go, you’ll probably find a crowd, with neighborhood families toting camping chairs and chalk for their kids to form what Shepard describes as an “impromptu sidewalk daycare.” When I dropped by at 4:15 p.m. last month, there were already around 50 people in front of me. Shepard — after fixing his neighbor’s mower — walked along the sidewalk encouraging people to leave the line to grab beer and wine.

“And when they get back, be cool and let them back in line, Ok?” he said.

Proletariat Butchery serves its Butcher’s Burger from 4 p.m. until sold out on the last Friday of each month at 5820 S.E. Foster Road. The next event takes place this Friday, June 26.

— Michael Russell; mrussell@oregonian.com

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