Julia Collin Davison, the shutdown’s effect, and a visit to Fiona

America’s Test Kitchen host Julia Collin Davison drops by to talk recipe testing and Cook’s Illustrated, which recently turned 25. We’re also looking at how the federal government shutdown affects what’s on our plates. Plus: Bill Addison weighs on Fiona while Bill Esparza gives us the 411 on his recent taco finds around the city.