One of the first things to like about Tracie McMillan, the author of “The American Way of Eating,” is her forthrightness. She’s a blue-collar girl who grew up eating a lot of Tuna Helper and Ortega Taco Dinners because her mother was gravely ill for a decade, and her father, who sold lawn equipment, had little time to cook. About these box meals, she says, “I liked them.”

Expensive food that took time to prepare “wasn’t for people like us,” she writes. “It was for the people my grandmother described, with equal parts envy and derision, as fancy; my father’s word was snob. And I wasn’t about to be like that.” This is a voice the food world needs.

Ms. McMillan, like a lot of us, has grown to take an interest in fresh, well-prepared food. She’s written for Saveur magazine, a pretty fancy journal, and she knows her way around a kitchen. But her central concern, in her journalism and in this provocative book, is food and class. She stares at America’s bounty, noting that so few seem able to share in it fully, and she asks: “What would it take for us all to eat well?”

The title of Ms. McMillan’s book pays fealty to Jessica Mitford’s classic of English nonfiction prose, “The American Way of Death” (1963). Ms. McMillan’s sentences don’t have Mitford’s high style — they’re a pile of leeks, not shallots — but both books traffic in dark humor. Standing in a Walmart, where she has taken a minimum-wage job, Ms. McMillan observes that its “produce section is nothing less than an expansive life-support system.” Most days, when it comes to vegetables, she’s putting lipstick on corpses.