WILLISTON — Rocky’s Burgers, Franks and Fries opened its third North Dakota location Monday morning in the former Slim Chickens building in Williston Square.
Mike Sartwell, president and CEO of Preferred Restaurant Group, which owns Rocky’s and was the Slim Chickens Williston franchisee, opened his first Rocky’s restaurant in Minot two years ago.
“As soon as that was a success, we knew we wanted to come to Williston,” he said. “We love doing business here.”
In the meantime, Sartwell opened the second Rocky’s restaurant in Fargo last November.
Sartwell has had an entrepreneurial presence in Williston for years, dating back to when his company purchased the Taco John’s franchise in Williston, then located behind Simonson’s. That restaurant moved to its current location on Second Avenue West in 2005.
The Slim Chickens franchise in Williston opened in April 2022. Earlier this year, Preferred Restaurant Group announced the restaurant would close in August. The location was one of his weaker performers financially, making the decision to rebrand straightforward, Sartwell said Monday morning. The building was renovated in preparation for Monday’s grand opening and ribbon-cutting ceremony.
What separates Rocky’s from its competitors is explained in its motto, “Fresh, Fast, North Dakota Roots,” which also serves as the restaurant’s philosophy.
The “fresh” covers the menu: never-frozen ground steak for the steak burgers, all-beef hot dogs in natural casing, chili made in-house, fresh-cooked bacon and sauces made from scratch. The restaurant has also added jumbo chicken tenders and wings, both fresh and never frozen.
Upon entering, customers are greeted by boxes brimming with Idaho potatoes. According to a sign sticking out from a box, the taters are “future fries.” Before the ribbon-cutting ceremony began, an employee rolled out a cart and loaded spuds for the kitchen.
Owner Mike Sartwell speaks during the ribbon cutting ceremony at Rocky’s Burgers, Franks and Fries on Monday, Sept. 14, 2026.
James C. Falcon / Williston Herald
The “fast” is the system built around that menu.
“We kind of bridge that gap between people that want a really high quality, fresh product, and they want it with the convenience of a drive-through,” Sartwell said.
The final part of the slogan, he said, is about hospitality — North Dakota service, with guests treated like family from the moment they walk in the door.
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Community giving is also built into the brand through a program called Round Up with Rocky’s. Each quarter, the company selects a local nonprofit and invites customers to round their orders up to the nearest dollar. Rocky’s matches every donation penny for penny, Sartwell said.
Between the Minot and Fargo restaurants, Sartwell estimated the program has returned just over $160,000, including the match, to local communities since opening.
The Williston restaurant’s first selection is Toys for Tots, timed to the holiday season. Customers who round up between now and the first of the year will have their donations matched.
The approach echoes a cause Sartwell’s family has supported for decades. After his youngest daughter — now 28 — was born with cystic fibrosis, he began raising money for the Cystic Fibrosis Association through his Taco John’s restaurants, including a holiday campaign tied to nacho sales. Williston, he said, has raised more for that effort than any other market in North Dakota.
With the newest restaurant now open, Sartwell said his family is focused on expanding the Rocky’s brand.
“Our family is focused on growing the Rocky’s brand across North Dakota,” Sartwell said. “We plan to open some Slim Chickens in other parts of the state, but really, one of our major focuses is growing this brand so that we open up Rocky’s in every city in North Dakota.”
For now, expanding the restaurant’s presence outside North Dakota isn’t on Sartwell’s agenda.
“We’re really going to be focused on North Dakota first,” he said, adding that Rocky’s is a family business. “I have a hunch that I’ll retire before they do anything like that, but that’s up to them.”
Sartwell’s son-in-law serves as chief operating officer, while his son works in marketing. Sartwell said he had sold off restaurants in other states about three years ago and expected to wind down his career.
That is until his family convinced him to launch Rocky’s, he said.
The name was their idea, too.
“Rocky is my nickname. It was my son’s idea,” he said. “I didn’t want that to happen, but the family pushed me. They said it’s good to have a story, and this is our story.”
He added, “This is their business as much as mine, or even more. This has been a work from the heart for me.”
Dining and Cooking