As more natural foods retailers try to capitalize on the seemingly insatiable demand for fast food that’s also healthy and nutritious by getting into foodservice or expanding their selection of grab-and-go items, so too are restaurants trying out ways to capture this lucrative market. The race has been on to find the “next Chipotle,” with restaurants employing different models to attract that ubiquitous rushed customer who doesn’t want to feel guilty about what a hurried lunch means for health. Here's a look at some of them.