The Magic Food Bus
The MFB Smashburger — double-stacked Colorado angus on parmesan toasted brioche

March 15, 2025 · 4 min read

The Best Smashburger in Louisville, Colorado

What makes a real smashburger — and why the MFB Smashburger at Relish Food Hall in Louisville, CO has become the one people drive across Boulder County for.

The smashburger has taken Colorado by storm, and for good reason. There's something about pressing a loose ball of ground beef hard against a screaming-hot flat-top — letting it caramelize into a thin, lacy-edged patty — that regular burgers just can't match. We've been making ours this way since we opened in 2020, and at our counter inside Relish Food Hall in Louisville, CO, it's still the thing people drive across Boulder County for.

What actually makes a smashburger different

A true smashburger isn't just a flat burger. The smash has to happen fast — while the beef is still cold — on a surface that's genuinely hot. 450°F or above. That contact creates the Maillard reaction across nearly the entire surface of the patty, not just the edges. The result is more crust, more caramelized beef flavor, and dramatically less grey interior. You get a burger that tastes like it's been cooked on the outside without being raw in the middle.

It also changes the texture in a way that's hard to describe until you've had one. The edges get lacy and almost crispy. The center stays juicy. The cheese melts from the bottom up because it goes on while the patty is still in contact with the grill.

How we make the MFB Smashburger

We use Colorado angus chuck — 80/20, never leaner — formed into loose balls and smashed to order on our flat-top. Sharp American cheese goes on immediately after the smash so it melts into the beef. Special sauce, crisp lettuce, tomato, red onion, and a dill pickle on a parmesan toasted brioche bun.

The brioche is toasted in butter on the flat-top and pressed gently until it's golden. It holds up without going soggy, which is the other thing most burger buns fail at.

Ours comes double-stacked. Two patties, two cheese slices, one bun. You can add crisp bacon (+$2), go for a third patty (+$3.25), swap to a gluten-free bun (+$2.75), or load on grilled onion or mushroom (+$0.50). It comes with house-made fresh fried potato chips — sub shoestring fries or crispy tots for $2.

The MFB Smashburger: $16.25

We set the price to reflect what goes into it: Colorado beef, real brioche, fresh vegetables, and a sauce we make ourselves. A smashburger at this price point at a fast-casual counter in Louisville is a fair deal. You're not paying restaurant markup, but you're getting restaurant technique.

If it's your first time, order the double smash straight — no modifications. Get to know the burger before you start building on it. Then come back and try it with bacon and jalapeños.

Find us at Relish Food Hall in Louisville, CO

We're inside Relish Food Hall & Pickleball at 550 McCaslin Blvd, Louisville, CO 80027. Open Monday through Sunday, 11am to 8pm (9pm on Fridays and Saturdays). Order ahead through GoTab or walk up to the counter — we'll have it ready fast.

If you've been looking for the best smashburger in Louisville, Colorado, or a great burger near Relish Food Hall, we'd love to be your answer. Come hungry.

Come try it yourself.

We're at Relish Food Hall & Pickleball, 550 McCaslin Blvd, Louisville, CO. Open daily 11am–8pm (9pm Fri–Sat).