A blend of roasted Anaheim, poblano and jalapeño chiles with onion, garlic, tomatillos and tomatoes, Qdoba's Chile Verde is its spiciest dish yet.

“South of the border, chile verde is an earthy, warming stew with a lot of flavor, which I thought would be a great cool-weather LTO for Qdoba,” Stoner says.

He roasted Anaheim, poblano and jalapeño chiles and combined them with sauteed onion and garlic, made a roux, and added stock, tomatillos and roasted tomatoes. He added chipotle chili powder and green chili powder for extra kick and chunky green peppers for texture.

The Chile Verde, which went into test at 100 of Qdoba's 475 units in March, is doing well. A week after introduction, 95 percent of guests surveyed gave it a “good” or “great” rating for flavor; 93.5 percent said they would buy it again; and 20 percent said they would visit more frequently for the dish.

Qdoba is testing the dish in Boston, western Michigan, the Seattle area and Colorado. Stoner says, “I knew we had a winner when a gentleman from Hidalgo, Mexico, tasted it and broke out in a big smile, saying, 'Tastes just like something from home.'”

Although chile verde recipes often include pork, Qdoba chose to keep its version vegetarian. “We have had good feedback on our bean and grilled vegetable recipes, which are meatless, so it was a natural to keep this recipe vegetarian, too,” says Stoner.

Stoner says he had a hunch that offering another “bowl” entree would do well for Qdoba. Thirty percent of guests already order their burritos “naked,” in a bowl.

He had experimented in the kitchen with a chile verde sauce that could be added to burritos. “But we would have had to make it too incendiary to have enough flavor and flow-through with all of the other ingredients in a burrito,” he says.

If Chile Verde finishes out the 2009 test well, Qdoba plans to offer the stew for two to four months each year as a cold-weather alternative to tortilla soup.

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