Bourke Street Bakery co-founder Paul Allam put seven intensive years of research into smash burgers in the US. The fruits of that investment will be unveiled today when his latest passion project, Hi Hi Burger, opens at Bondi Junction.

There’s a lot to get excited about at Hi Hi, where they use Vic’s Meat and a single smash burger is an affordable $7.90. (That’s less than a Macca’s Big Mac or Quarter Pounder at some locations, whose price can vary but cost $8 or more at some outlets.) Allam also backed his Bourke Street Bakery experience to update the potato bun, ubiquitous in US smash burgers: “I thought we could improve it,” he said.

Allam moved to the US to launch Bourke Street Bakery NYC, with its four stateside outlets now established enough for him to relocate to Sydney. The experience taught him some lessons about the US market: while Bourke Street’s sausage rolls have been a hit, pies remain a hard sell because consumers in New York associate “pies with sweet over savoury”. It also taught him plenty about US street food.

Returning to Australia, he missed some of the staples of his life living in Brooklyn, although he points out Sydney has some good smash burgers. While Allam can’t accurately count the number of burgers he consumed on his US smash burger hunt, what made a great burger of the smash genre became evident.

“You have to use good meat,” he said of the first step. “And you have to smash them properly.” The temperature of the grill is critical, so the ball of meat gets a proper crispy edge and doesn’t stew.

“There are different schools of thought,” Allam said about how onion is included. Some smash the meat on cooked onion on the grill, whereas Hi Hi incorporates onion into its patties. Some places shave onion on the top, which Allam might do later as a special.

Hi Hi has kept the menu simple, with the staple beef burger adorned with American cheese, pickles and special sauce. There’s a vegie smash burger made with quinoa, chickpeas and carrots.

The burger start-up has nabbed a site just off Bondi Junction’s Oxford Street Mall, on the ramp that leads to the train station and bus interchange. “It’s small, it’s fun, it’s very limited,” he said.

Allam and his Bourke Street Bakery co-founder David McGuinness have long had an adventurous spirit with side projects, opening a restaurant and launching social enterprise bakery The Bread & Butter Project.

Allam’s smash burger “passion project” could be the first of a few ventures reflecting his time in the US. He points to his local food passions while living there as smash burgers, pizza by the slice, and barbecue.

He bought a smoker to try his hand at barbecue. “The only way to make good brisket is to make bad brisket,” he said of his education. But he’s getting close.

With his bakery background, pizza by the slice is an easier proposition. Sydney could get a taste of Allam’s version before the end of the year at Paulies, which will open in the development on the corner of Oxford and Crown Streets, Darlinghurst.

Open Tue-Sun noon-9pm (Limited hours this week: Tue-Fri 3-9pm)

5/424 Oxford Street, Bondi Junction, hihiburger.com