A single onion burger, with everything on it, including house-made pickles and pickled jalapeños

Considering it’s shaped like a sauce pan, we rarely see a cooking tradition attributed to Oklahoma. Yet, sure enough, when I google the term “onion burger,” all results credit the Sooner State.

I might never have known if not for a new La Mesa joint called Duke’s Old Fashioned Onion Burgers. Don’t all burgers have onions on them?, I thought, as I approached the place. What makes them old fashioned anyway?

As I’ve since learned, the onion burger is a style created nearly a century ago, in response to a distinct point in American history: the Great Depression. As the story goes, high beef prices prompted a burger spot on historic Route 66 to start making burgers with smaller patties, filled out by copious amount of grilled onion.

The burger patties are formed smash-burger style, meaning a ball of ground beef is pressed on a hot griddle, creating a thin, irregularly shaped patty with a high char ratio. While this style has become fairly widespread in San Diego, what makes it an onion burger is when the burger gets flipped, a big mass of sizzling, finely sliced onion cooks down between burger and flat top.

A simple, independently-owned fast-food restaurant in La Mesa

In its original design, the texture and flavor of all that grilled onion made up for a relative lack of beef. However, whereas Duke’s remains faithful to the onion burger concept, it’s not here to skimp on beef. Whereas most smash burger patties weigh in between two and four ounces, the heft of Duke’s $8.95 single onion burger has to put it in the six- to eight-ounce range. If you’re a big eater, the substantial, $11.95 double onion burger starts to look like a real value. A $14.95 triple is so large, even its menu description asks, “What were you thinking?”

Perhaps with a regular, $3.25 side order of fries, I could finish a double. But Duke’s has an entire fries menu that must be factored in. It starts with dirty fries as simple as fried with onions and jalapeños ($4.95) or smothered in melted cheese ($6.50), then peaks with toppings of steak, blue cheese, and balsamic glaze ($11.95). Somewhere in the middle there sits my favorite guilty pleasure: chili cheese fries. You get a huge pile of fries and chili sans beans for $7.50, and they’re darn near perfect. I’d recommend Duke’s based on these alone.

A strawberry milkshake with fresh strawberries blended in

I’d also point people here merely to try the milkshakes. Yes, they go for $5.50 apiece, but what you get outperforms every fast-food milkshake you’ve encountered in your life. The Death By Chocolate mixes Hershey’s syrup into its chocolate ice cream. Even better, the Field Fresh Strawberry milkshake is blended with fresh strawberries. I want all my shakes like this from now on.

Still, at the top of a list of reasons to visit Duke’s is the onion burger. I don’t know how similar it to anything made in Tulsa. I do know this thing is a burger lover’s dream. It becomes more apparent with each bite that every ingredient, and every detail, has been carefully considered with an eye toward making this deceptively simple burger taste better, whether it’s the tender richness of a locally baked brioche bun, house-made pickles adding the perfect zest, or the ideal ketchup to mustard ratio (no thousand island dressing here).

A massive plate of chili fries for $7.50

The beef isn’t wagyu, or dry aged, or advertised as a special custom blend — though I’m told it is angus beef shipped from Tennessee. It’s not even heavily seasoned. But combined with the classic assortment of burger toppings (pickled jalapeños optional), it results in a sandwich greater than the sum of its parts. Plus, just look at all that glistening, grilled onion! Thanks, Oklahoma.