We head to the kitchen to answer cooking and food questions. Why does food taste better with salt? Why do we need salt to make sweet things like cookies? Why do seasonings taste good in food but not so much on their own? Why are marshmallows soft? Why do egg whites go from clear to white when they're cooked? How are expiration dates determined? Answers to your food questions with Molly Birnbaum, host the podcast Mystery Recipe and editor of America's Test Kitchen Kids.