A Westerner visiting China in the 1990s could expect dinner hosts to offer their guest “salad” alongside regional foods like Sichuan mapo tofu or Hunan red-braised pork. The then out-of-place dish was both a sign of respect for the visitor and a way of showing that China was opening up to “outside” ideas, even about cuisine. Yet, a Chinese offering of “sè-lā,” as the dish is pronounced in Mandarin, would often remain untouched. What passed for salad—diced potatoes tossed with Russian dressing, or a half-head of doubtful-looking iceberg drenched in an indeterminate glop—wasn’t very appealing alongside traditional Chinese fare.

Credit Frenchman Xavier Naville for better orienting salad in China. In “The Lettuce Diaries,” Mr. Naville recounts his unlikely story of creating a market there for the kind of salad greens familiar to Westerners.

When he arrived in Shanghai in the summer of 1997, the 27-year-old Mr. Naville was the impeccably dressed but woefully inexperienced head of finance for Asiafoods, a British-backed American startup that, like Sysco or Aramark, packaged “safe, hygienic meals” for “institutional canteens.” Within two years he had learned not only rudimentary Mandarin but also “all about the challenges with vegetable sourcing and growing in China—in both supply and hygiene.” He had also chanced upon a promising client, KFC, which needed a Chinese supplier of coleslaw and lettuce for its already more than 300 fast-food chicken restaurants on the mainland.

In the year 2000, Mr. Naville and an American vegetable-prep consultant spun off a few stainless-steel chopping tables at Asiafoods into a new venture, Creative Food, that would become, in Mr. Naville’s words, “the largest fresh-food company in China.” Bite into a chicken sandwich at a KFC in Shanghai today, or buy a bagged salad in a supermarket in Beijing, and there’s a good chance the operation Mr. Naville launched supplied the lettuce inside.

Until the advent of Western-style fast food in the 1990s, “the Chinese rarely ate raw vegetables,” Mr. Naville remembers. “I knew from our canteen menus that to them, raw food was not food, period.” But once urban diners acquired a taste for burgers and fries, raw salads became less of a stretch. Young, newly affluent Chinese consumers soon came to like bagged, chopped, pre-washed greens because they were as convenient as fast food but far more nutritious. “They were a new form of healthy food that preserved more vitamins than stir-frying vegetables in the traditional Chinese way,” Mr. Naville writes. Within seven years of its launch, he had sold Creative Food at a $20 million valuation.