Take it from Stephen Trojahn, co-owner of one of Minneapolis' longest-running food trucks, Gastrotruck: "Business is amazing."

Gastrotruck (gastrotruck.mobi), which will celebrate a decade in business next year, is on to its third truck. This summer, it'll cater some 200 weddings with an on-call staff of up to 60 people.

Now, it's joining other food trucks in the move to a brick-and-mortar establishment.

The new counter-service spot, scheduled to open in Minneapolis this summer, is called Carbon. (The exact location is still under wraps.)

"It's coal-fired pit beef," Trojahn said. "It's considered Maryland barbecue, but it's nothing like barbecue at all."

Inspired by East Coast roadside stands, fast-casual Carbon will serve paper-thin-sliced beef sandwiches with a horseradish-based "tiger" sauce.

"The quality of the beef coming off a carbon-fired grill, shaved super thin, it melts in your mouth," Trojahn said.

The restaurant will offer variations on the sandwich using the same live-fired beef: Philly cheese­steak, Italian beef, French dip; and veggie sides such as grilled whole carrots. There will also be Maryland-style "boardwalk" fries topped with Old Bay seasoning and malt vinegar.

Co-owner Catherine Eckert grew up in Maryland. "We did a research trip there, and I was blown away," Trojahn said.

The new concept is good news for fans of Gastrotruck, which doesn't often appear on the downtown Minneapolis lunch scene. Trojahn and Eckert got out of that "rat race," as Trojahn calls it, in favor of the catering business, which he says has exploded.

Brick-and-mortar wasn't always in the cards, though. They were just too busy. "It's a good problem to have," Trojahn said.

He believes the food-truck business is going strong because it gives diners something they can't get anywhere else.

"People love one-on-one interaction," he said. "There are two or three people on a truck, and one is possibly the owner and one is the cook. You might be talking to the people making your lunch. You don't get that in a restaurant."