Some time ago, McDonald's realized it had a "freshness" problem. Its younger customers, age 18 to 32, were opting for fresher, seemingly healthier options from competitors like Subway and Chipotle. So in April of this year, McDonald's debuted the McWrap. Bloomberg Businessweek reporter Susan Berfield got an inside look at McDonald's test kitchen, which spent nearly two years focus-grouping the new product. She joins Take Two with her story.