Juju, who seems to possess his mother’s charisma and makes frequent cameos on her show, was not looking forward to it.

“I have the best Mexican food at home,” he explained, “so I don’t need to go to Taco Bell.”

Food is Ms. Jinich’s third career, if you include motherhood. A dozen years ago, she was trying to put her master’s degree in Latin American studies from Georgetown University to use writing policy papers for Inter-American Dialogue, a think tank focused on Latin America and the Caribbean.

She dreaded going to work, except for the part where she got to think about lunch. One day, she was asked to compare the transitions to democracy in Peru and Mexico, but instead went deep researching the differences between Peruvian and Mexican ceviche.

That’s when she knew. “Instead of writing about strengthening democratic institutions in Mexico,” she recalled thinking, “how about I write about the food of Mexico?” She enrolled in night school at L’Academie de Cuisine in Maryland, which is now closed.

Cooking didn’t come naturally to her, although her three older sisters are in the business and her father, Moises Drijanski, is a larger-than-life kind of guy who ran two restaurants in Mexico City. He would sneak jam and caviar home in his suitcase, and once fed the family so much fettuccine at Alfredo’s in Rome that the chef came out to see who was eating it all.

Many in the family were surprised that the youngest child — the studious, serious one — would become a food star. But not her dad.