The Crunchy Hippie
If she is a vegetarian, I'd send you to Amanda Cohen's lovely but unfortunately-named Dirt Candy. There's nothing virtuous about the food here, but Cohen really shows the range a veg-only palette can achieve with dishes like a cheeky faux gras.
But she'd probably be equally smitten with a cheap falafel, scarfed in the park within earshot of her busker guitarist friend. For that I'd recommend Taim (222 Waverly Pl.), easily the best falafel in New York City. If she's supremely crunchy though, you might consider staying home: Whip up some co-op–sourced quinoa and compare carbon footprints over mug-fuls of kombucha.