TV’s smartest chef, Alton Brown, is ending his blockbuster show after more than a decade. More than 250 episodes later, Brown has achieved his goal of tutoring the masses, introducing terms like “hygroscopic,” “Maillard reaction,” and “polyphenol oxidase” into the vocabulary of the average home cook. He was the first TV food personality to get cerebral about groceries, helping viewers get to know the properties of ingredients and how best to manipulate them for maximum taste. (What other chef would use Tinkertoys to explain sugar crystallization?) Brown and his wife, DeAnna, built the Good Eats empire from scratch, shooting the...