Michael Harden learned during his long career as a commercial lobsterman that there are only three components needed to make a good lobster roll -- lobster, butter and roll.

But as it became too difficult for Harden to bank on harvesting the sandwich's most salient ingredient on his boat in Norwalk, he turned instead to a sector of the food industry that was growing nearly as fast as lobster fishing was waning -- food trucks.

Urged by his wife to give cooking lobster rolls a try, Harden purchased a battered truck from Indiana in 2012 and spent four months cleaning and hand-painting the vehicle before taking the nascent LobsterCraft out on the roads of Fairfield County. When the demand became overwhelming, he enlisted Trond Fletcher, a friend of 30-odd years with a family history in the food business, to copilot the venture.

"We always say food trucks are the pirates of the culinary world," Fletcher said.

Since 2012, LobsterCraft has peddled a simple menu of lobster rolls in Fairfield County, attracting a throng of 100 customers on a good day. Now, the seafood venture is setting down permanent roots, an oft-longed-for goal in the food truck business. The first LobsterCraft restaurant is set to open in a 600-square-foot storefront on Tokeneke Road in Darien in the next few weeks, with another location preparing to launch in New York City this fall. LobsterCraft's two trucks, painted with bright orange lobsters, will continue to run from Greenwich to Westport.

"It's been a crazy growth pattern," Harden said. "I think we really hit a niche with gourmet lobster rolls that needed to be filled."

It seems Fletcher and Harden entered the business at a particularly opportune moment. Over the past five years, the food truck sector has been growing at a steady rate of 12.4 percent a year, an unusual beacon of success in a restaurant industry that struggled during the recession, according to market research by IBISWorld. In Connecticut, food trucks have been trawling the roads for customers since the mid-1990s, but the concept has only really taken off in Fairfield County over the past seven or eight years, said Linda Kavanagh, director of the New England Culinary Group in Stamford.

"The transitions come from either angle; a chef with an established restaurant/name taking their act on the road or a successful food truck morphing into a full scale operation," Kavanagh said. "The challenge is that the truck and the restaurant have zero similarities and both have their unique set of business components."

For LobsterCraft, the idea to establish a physical location came through customer demand. After a long search for a location, Harden and Fletcher bought out the space previously occupied by a deli next to White Bridge Wines and Spirits. The operation will be small. A staff of four or five will work in both the restaurant and the two trucks, with room for more hires, Fletcher said.

"Everybody asked if we were just a truck, so it really came from the crowd," Harden said. "There's not a lot of food trucks out there that say they're happy with just a truck."

Though the Sound's lobster industry may only yield a fraction of its former catches, LobsterCraft still sources local ingredients whenever possible. The rolls come from Muro's Original New York Bakery in South Norwalk and LobsterCraft has relationships with a number of local farmer's markets, both to buy produce and to sell the finished product at the markets. The most pared-down lobster roll on the menu starts at about $16, but the price really depends on the market, Fletcher said.

As a food truck, LobsterCraft closed up shop in January and February to refurbish the equipment and prepare for the coming spring season. But the Darien restaurant will be a year-round operation.

"This is my cruise ship," Harden said.