In this week's Flightless Bird, David Farrier talks to the author of 50 Pies 50 States, Stacey Mei Yan Fong. Farrier sets out to discover why Americans love pie so much, declaring January 23rd National Pie Day back in 1986. Farrier and Fong discuss what makes the pie so American, before looking at Stacey’s top 3 American pies - which David, Monica and Rob then sample.