A young man named Ihashi Satoru graduates at the top of his class from cooking school and joins the kitchen of Fujimura, a traditional high-end Japanese restaurant located in Shinjuku, Tokyo. Fueled by his academic success and a cocky, hot-headed personality, he expects to immediately work with a knife. Instead, he is assigned the lowest position in the kitchen: the oimawashi, or apprentice, whose duties consist of washing dishes, running errands, and handling other menial tasks. Frustrated and rebellious, Ihashi initially resents the feudal hierarchy of the kitchen and clashes with his senior coworkers.

His turning point comes when he is challenged to a vegetable-peeling contest by his quiet, hardworking peer Tanizawa Makoto, who is the same age but has years of practical experience. Ihashi loses decisively. More importantly, he tastes the cooking of the head chef, Kumano Shinkichi, and realizes the depth of his own ignorance. Humbled, he decides to commit himself wholeheartedly to the path of a professional chef. The series follows his daily life at Fujimura, where he learns not only technical skills but also the importance of heart, respect, and an unending dedication to the craft of Japanese cuisine.

The core setting is the kitchen and private dining rooms of Fujimura. The main characters include Ihashi, the impulsive but increasingly dedicated protagonist; Tanizawa, his quiet and diligent same-age senior; the stern but fatherly head chef Kumano, who runs the kitchen with a white towel around his neck; Bon-san, an elderly former monk with a mysterious past who works the fry station and speaks in Kansai dialect; and a rotating cast of other chefs, including the tough senior Yokogawa and various apprentices who come and go. The restaurant is also populated by veteran waitresses and a colorful group of regular customers, including a rakugo storyteller and a small-business owner who often find themselves mediating conflicts in the dining room.

The narrative arc of the original series, written by Zenta Abe and illustrated by Yoshimi Kurata, follows Ihashi from an arrogant rookie into a reliable chef who eventually leaves Fujimura to train in Kyoto and other locations, always seeking to deepen his understanding of food. After Abe's death in 1999, the story continued through multiple sequel series. In Aji Ichi Monme Dokuritsu-hen, Ihashi becomes the hired manager of a restaurant in Kagurazaka. In Nippon Shoku Kiko, he embarks on a journey across Japan to explore regional ingredients and cooking traditions. In Sekai no Naka no Washoku, he examines the role of Japanese cuisine in a global context. The most recent series, Tsugi Aji, sees him return to his home base of Fujimura after learning that the aging Kumano has fallen ill, and he takes on the role of mentoring a new generation of young apprentices while continuing his own studies.