The year is 2015. Millennials have yet to be admonished for buying avocado toast, and they leave parties in $10 Uber pools before posting, earnestly, about their nights on Instagram because Stories do not yet exist. On Bleecker Street in Greenwich Village, Chloe Coscarelli, a Cupcake Wars winner and author of a handful of vegan cookbooks, has opened the counter-service spot By Chloe, selling quinoa tacos, macaroni and “cheese” with shiitake bacon, air-baked sweet-potato fries...