At Smash That Burger, a truck in permanent park outside Rooftop Brewing Company, cooks press patties onto a hot griddle with conviction. Layer one on top of another and the crisped, lacy edges become a veritable geographic formation of beef, rippling outward from a standard-size burger bun. Somehow the center remains juicy. American cheese and a pickly house sauce trickle down the burger’s unruly sides.

A proper smash burger vaults above the sum of its griddled, melty parts. It’s an act of burger greatness. It’s also, annoyingly, a buzzword, often attached to specimens that are about as smashed as Rod and Todd Flanders on Easter Sunday. This neon yellow truck, not far from the Ballard Bridge on Queen Anne’s north slope, is only open a handful of days right now, but puts out a smash burger that restores your faith.

Seattle has beer and coffee—its dual beverage poles—to thank for Smash That Burger. Owner Jack Kelly is also the founder and CEO of Caffe Ladro. Its roastery on Nickerson Street occupies the same building as Rooftop Brewing. The two staffs intermingle in the open warehouse. Brewers use Ladro’s coffeemaker; Rooftop supplies the roasters’ after-work drinks. Kelly would occasionally cook smash burgers for everyone on a portable griddle.

He wasn’t exactly looking to start a burger business, much less a food truck. But he watched Rooftop struggle to manage a rotating calendar of food trucks—the standard way Seattle breweries provide food for taproom visitors. Rooftop co-owner Craig Christian wanted to install a kitchen so the brewery could do its own food. When that proved too expensive, Kelly got serious tinkering with his smash burger recipe. If this sounds like an overreaction to a problem that wasn’t even technically his, well, Kelly admits that he also saw Smash That Burger as a potential test case, should he ever decide to diversify his portfolio beyond coffee.

Also, he loves burgers. And with a job that’s mostly about oversight, it was nice to be hands-on with a project once again—“I’m a barista at heart,” says Kelly. “But I don’t get to be a barista anymore.” He won’t say which of the 20-ish patty-smashing implements he tested emerged as the gold standard. But the implement cooks use to get those flattened-out patties off the griddle is essentially a large putty knife, the kind you buy at Home Depot—"you have to really get underneath there.”

Food trucks and taprooms have long enjoyed a symbiotic relationship, the trucks sustaining drinkers while letting brewers avoid the hassles of getting into the restaurant business. But setting up a rotating schedule can be its own full-time job. Rooftop originally signed up with seattlefoodtruck.com, which lets trucks sign up for slots at various breweries (this setup remains in place when Smash that Burger isn't open). Christian wanted more consistency, and food that complements beer. And, with a dozen breweries concentrated across the bridge in Ballard, “smash burgers make this more of a destination for people.”

The same iterative approach that drives Ladro’s roasting helped Kelly dial in the bun (Franz), the grind (prepped at Ladro’s baking commissary), and the American cheese (“there’s a wide range of quality and thickness”). The resulting burger might resemble Jabba the Hutt, but the pressed patties are delicate, and the bun smooshes down to practically nothing between your fingertips—the whole thing feels superbly calibrated, not just another mindless act of beef swagger.

Kelly unearthed a few semi-obscure regional burgers for the concise menu. One’s a tribute to Oklahoma’s Depression-era onion burger, though the diaphanously thin sliced onions mostly layer nuance into a really good cheeseburger. The Chester, a deep cut from Long Island, is essentially a grilled cheese sandwich, on Texas toast, with a burger in the middle. A jalapeno burger crackles with both pickled and crispy-fried peppers, but restrained amounts of actual heat. People customize with extra patties, or by subbing Beyond Beef in for meat.

Kelly repped his own childhood in Minnesota by making sure his truck serves crinkle-cut fries. (Which hold up reasonably well for takeout orders.) Fry options start with basic-but-not-boring salt and pepper. Other versions level up with spicy seasoning, sauce, piles of grilled onions, then the mightiest “totally smashed” option that basically throws every part of the jalapeno burger—including the patties, but minus the bun—atop a pile of fries. As gluten-free options go, this feels more fun than wrapping a burger in a lettuce leaf.

Burgers here are absolutely a destination, but also a good reason to hang out at Rooftop, with its relaxed patios and plentiful pints of La Azotea lager or Gateway hazy pale ale. As one companion observed, “It’s like going to a brewery in Ballard before Ballard became Ballard.” And like eating a smash burger before they became a smash hit.