DENVER – Following through on its pledge to build out its menu, Chipotle Mexican Grill Inc. this week added quinoa at its New York City test kitchen. The test kitchen opened in July 2017 and serves as a venue for the quick-service restaurant chain to try out new menu items before rolling them out on a national scale.

Chris Arnold, communications director at Chipotle

“The quinoa is made with red and gold quinoa tossed with a little citrus juice, cumin and freshly chopped cilantro,” Chris Arnold, communications director at Chipotle, told Business Insider. “We are recommending that it be added to a salad, or in place of rice in another entree.”

Earlier this month during a conference call to discuss fourth-quarter results, M. Steven Ells, founder, chairman and outgoing CEO of Chipotle, said the company would continue to look at ways to improve its menu.

Steven Ells, founder, chairman and CEO of Chipotle

“I think the next team’s biggest opportunity is to always look at our core menu and make sure that we’re cooking better food,” Ells said. “We’re sourcing better food. We have better ingredients. We’re improving our preparation techniques, our cooking techniques, our serving techniques. It’s what drove our business for the first couple of decades, taking a core group of menu items and continually improving them, not only through Food with Integrity but through a better restaurant execution. So that’s a priority.”

But improving the menu is not without its challenges, Ells said. Turnaround efforts have been met with tepid response at the restaurant chain. Introductions of chorizo and queso have failed to deliver on expectations. During the Feb. 6 conference call with analysts, Ells elaborated on the challenges of adding new menu items at a company like Chipotle.

“The new menu items at a place like Chipotle is tricky, though,” he said. “It’s tricky not only because we’ve had the same menu for basically 25 years but because of the linear format. It’s not like you can put a whole new thing up on the menu board … like at a typical fast-food place. Ingredients sort of become part of the overall offering. So, it’s a tricky proposition, but it’s something that we’re working really, really hard on. There are exciting new offerings that are around things like salads and different kinds of grains and also an exploration of traditional things, like — and these are things that customers are asking for — things like nachos and quesadillas. And so how to integrate those into our service format so that we can maintain throughput and sort of the level of execution that we relied on in the past is tricky.”

Quinoa is a “pseudo-cereal,” or a food that is cooked and eaten like grains and has a similar nutrient pro?le, according to the Whole Grains Council, Boston. The Incas in South America considered quinoa to be the “mother of all grains.”

Mostly grown in the Andes in South America, quinoa is gluten-free and offers all the essential amino acids, according to the Whole Grains Council, which said quinoa in North America is being grown in areas of the Rocky Mountains, from Colorado to Saskatchewan, mostly at elevations of 7,000 to 10,000 feet.

Quinoa has been garnering interest in mainstream outlets for several years. US retail sales of products featuring quinoa increased at an average annual growth rate of 72 percent from 2012-16, going to $552.9 million in 2016 from $69.3 million in 2012, according to Nielsen Scantrack data. The top-selling items in 2016 were snack bars ($113.6 million), bagged/box quinoa ($79.6 million) and ready-to-eat cereal ($69.7 million).