First, He Conquered Paris. Now, a Japanese Chef Wants to Become a Brand.

In cooking, timing is everything. So much so that if the chef Kei Kobayashi spots diners heading to the restroom as he sends a dish out from the kitchen, he stops them. Nature’s call can wait; his culinary offerings should be tasted at peak flavor.

Such imperiousness and exactitude align with what Mr. Kobayashi, the first Japanese chef to earn three Michelin stars for a restaurant in Paris, said he had learned from one of his earliest mentors in France: The chef is king.

“Unless you commit to your worldview to this extent, you won’t be able to be a chef,” Mr. Kobayashi, 46, said during a recent interview in Tokyo.

Having earned his third star — the maximum — for his Restaurant Kei in Paris in 2020, he has now expanded his ambitions back to Japan, where he has opened four restaurants over the past two years.

The goal, Mr. Kobayashi said, is to become a brand. In that sense he seems to be emulating Alain Ducasse, at whose now-closed Paris restaurant, Plaza Athénée, Mr. Kobayashi worked before opening his own in 2011.

He also joins a line of creative Japanese — including the artists Yayoi Kusama and Takashi Murakami — who first found fame outside their homeland.

Mastering the art of French cooking has become something of a Japanese specialty. In Tokyo, which has more Michelin-starred restaurants than any other city in the world, four of the dozen restaurants awarded three stars feature French cuisine.

Mr. Kobayashi wants to show how French food can evolve with seasonal Japanese ingredients, he said in the interview, just hours before the official opening of Kei Collection Paris, his new restaurant on the top floor of the Toranomon Hills Station Tower in Tokyo.

At Kei Collection, he has sneaked some classic Japanese comfort dishes onto the menu, including curry and breaded beef cutlet, alongside fancier items like butter-roasted large clams, smoked bonito with white cheese foam, or delicate hand rolls of tuna and caviar.

For the restaurant’s opening, Mr. Kobayashi, his hair dyed platinum blonde, wore a traditional chef’s double-breasted white coat embroidered with three Michelin stars over black trousers and green suede New Balance sneakers. An Audemars Piguet watch was strapped to his wrist.

He spoke modestly, rejecting descriptors like “first class” or “genius” and saying he never allowed himself to think he had reached the pinnacle of cooking. But Mr. Kobayashi appeared coiled and a little aloof, belying his humble words.

His uncompromising approach is embodied by what he said was his favorite French phrase: “aller plus loin” — go further.

“If you make a compromise, or think ‘OK, this is good,’ then it is time to quit,” he said.

His attention to detail extends beyond the food. “He cares about the furniture selection and the interior, the softness of the sofa,” said Tadashi Nobira, manager of Esprit C. Kei Ginza, another one of Mr. Kobayashi’s new restaurants in Tokyo. “He cares to the last centimeter.”

Just minutes before a guest arrived for a solo lunch with the chef on opening day at Kei Collection earlier this spring, Mr. Kobayashi was adjusting the volume of a curated jazz collection playing in the dining room.

Mr. Kobayashi grew up in Nagano in central Japan, where his father worked as a chef. His mother cooked homemade meals every night, including his favorite, curry rice. But Mr. Kobayashi said he did not learn to cook from either of them.

Instead it was a documentary about the French chef Alain Chapel that first captivated Mr. Kobayashi, who envied the chef’s crisp white jacket. Forgoing high school, he took a job at a local French restaurant, where, as he recalled, he spent four years in which “the chef just kept getting mad at me.”

At 19, Mr. Kobayashi moved to Tokyo to work for Ikuo Shimizu, a mostly self-taught chef who gave his apprentice basic training in how to work with meat and fish.

“He was very mischievous, but he had a strong backbone,” Mr. Shimizu said in an interview at his eight-seat restaurant in a quiet neighborhood in Tokyo, where he serves rustic French meals. “I thought he was really an artisan. He was particular about the details, like the shape of the knives and how to sharpen them.”

Having fixated on French cuisine, Mr. Kobayashi decided he needed to move to France. An acquaintance helped him land a job at Auberge du Vieux Puits in the Languedoc-Roussillon region, where he worked for four years under the tutelage of the chef Gilles Goujon, who has also earned three Michelin stars.

In a video interview, Mr. Goujon said he was immediately struck by the young cook with bleached hair.

With a touch of stereotyping about Japanese prowess, Mr. Goujon first assigned Mr. Kobayashi to the fish station, instructing him with gestures and cookbook illustrations. Even on days off, “he wanted to come and work,” Mr. Goujon said. “So we had to lock the restaurant so he could go and rest.”

After two seasons at the fish station, Mr. Kobayashi tried to convince his boss that he had developed allergies and needed to switch to meat and game. Mr. Goujon was amused, and he eventually moved Mr. Kobayashi to the meat station to learn how to debone birds, deer and wild boar.

Mr. Kobayashi also worked briefly at a patisserie in Provence and at a restaurant in Brittany. The latter didn’t go well, he said. “At the time, there was a movement to make French cuisine more scientific, and I didn’t agree with that,” he said. “I went to learn Breton cuisine, not science.”

He worked at Mr. Ducasse’s Plaza Athénée for seven years before going out on his own, buying a restaurant whose chef was retiring.

“Maybe I was stupid,” he said, “but I figured the cooking would work itself out.” He was worried, however, about whether he could support the staff he was hiring, who “were putting their lives on the line.”

Within a year, he earned his first Michelin star; the second came five years later. After the third, he decided to make the move back to Japan.

In addition to Kei Collection Paris and Esprit C. Kei Ginza, Mr. Kobayashi has opened a restaurant at the Ritz-Carlton hotel in Tokyo and one in Gotemba, near Mount Fuji. The Gotemba and Ginza restaurants are collaborations with Toraya, a centuries-old Japanese confectionary company.

With Mr. Kobayashi spending most of his time in Paris, he handpicked chefs to run the kitchens at the new Japanese restaurants, relying on them to develop dishes based on local ingredients.

Teruki Murashima, 50, the chef de cuisine at Héritage by Kei Kobayashi at the Ritz, said he talked frequently by phone with Mr. Kobayashi and sent him photos of dishes and lists of ingredients.

“We both may make completely different dishes with the same ingredients,” Mr. Murashima said in an interview at the Ritz. “But we know that about each other, and we respect each other.”

Still, Mr. Murashima said, Mr. Kobayashi is “very particular about certain things, and really gets quite angry if things don’t reach his standards.”

At times, Mr. Kobayashi is prone to remind customers of those standards. If a diner takes out a cellphone to snap a picture of a dish, said Mr. Nobira, the Ginza restaurant manager, Mr. Kobayashi might appear at the table, encouraging the customer to take a bite right away instead.

Is he, then, a king? “I might be close to one,” he said.

Ségolène Le Stradic contributed reporting from Paris.