Truong insinuates Stein and Toklas into Binh's story with telling glimpses of the women's relationship to each other and their treatment of their cook. For over three years, Binh lives with the Mesdames, viewing them with a queasy mix of awe and resentment. Stein comes off like a swaggering lifeforce; he is "enthralled by her upper lip with its black hairs twitching gently as she speaks." He doesn't realize that she's a notorious writer, only that she's something of a vampire, feeding on everyone around her, including himself. Toklas, on the other hand, is a sublimated character, foraging for rapture among the radishes in her garden: "I have heard her weep with the juices of the first strawberry full in her mouth."
The Book of Salt doesn't lay its secrets bare but coils itself around them. Truong leaps between scenes of Binh's pleasure and humiliation, using the language of gastronomy to communicate the daily indignities of servitude and colonialism. Binh is fiercely proud of his intimacy with his Mesdames, bragging, "I know the postcards that they collect and the women who recline naked on them. I know the old-women gasses that escape from them, and the foods that aggravate them." Yet all it takes is a moment of overfamiliarity and he's excommunicated from their good graces. "The sight of warmth fading from Miss Toklas's eyes is a glimpse of my own death. Suddenly, I am no longer there." His mistresses are allowed to be eccentric, but Binh must forever remain invisible, the ghost in the kitchen.