What has to happen for Vietnamese lemongrass barbecue sauce to take up as much space as Texas barbecue sauce on an American grocery store shelf? There’s a whole generation of young entrepreneurs — many of them women of color — making packaged foods that are expanding the palate of American shoppers. This week, live on stage in Brooklyn, Dan is talking with two of these businesspeople: Chitra Agrawal, founder of Brooklyn Delhi, and Vanessa Pham, the CEO of Omsom.