In Lyon, an ancient but benevolent law compels bakers to take one day off a week, and so most don’t work Sundays. An exception was the one in the quartier where I lived with my family for five years, until 2013. On Sundays, the baker, Bob, worked without sleep. Late-night carousers started appearing at three in the morning to ask for a hot baguette, swaying on tiptoe at a high ventilation window by the oven room, a hand outstretched with a euro coin. By nine, a line extended down the street, and the shop, when you finally got inside, was loud from people and from music being played at high volume. Everyone shouted to be heard—the cacophonous hustle, oven doors banging, people waving and trying to get noticed, too-hot-to-touch baguettes arriving in baskets, money changing hands. Everyone left with an armful and with the same look, suspended between appetite and the prospect of an appetite satisfied. It was a lesson in the appeal of good bread—handmade, aromatically yeasty, with a just-out-of-the-oven texture of crunchy air. This was their breakfast. It completed the week. This was Sunday in Lyon.

For most of my adult life, I had secretly wanted to find myself in France: in a French kitchen, somehow holding my own, having been “French-trained” (the enduring magic of that phrase). I thought of Lyon, rather than Paris or Provence, because it was said to be the most Frenchly authentic and was known historically as the world’s gastronomic capital. Daniel Boulud, the most successful serious French chef in the United States, was from there, as was Paul Bocuse, the most celebrated chef in the world. The restaurateur Jean-Georges Vongerichten had trained in Bocuse’s kitchen, as his sauce-maker. “Lyon is a wonderful city,” he told me. “It is where it all started. You really should go.”

Why not? My wife, Jessica Green, a wine educator and lecturer, lived for the next chance to pack her bags. (She also spoke fluent French, which I did not.) And our twin boys, George and Frederick, were three years old—possibly the perfect age to move to a new country. Our landing, though, was surprisingly rough. Lyon seemed unwelcoming, suspicious of outsiders, and indifferently itself. “Our town is not easy to love,” a Lyonnais novelist had written in the thirties (the Fascist Henri Béraud, who was also not so easy to love). “It is an acquired taste. Almost a vice.”

We got an apartment by the River Saône, situated auspiciously on the Quai Saint-Vincent. (Vincent was the patron saint of winemakers.) A gnarly first-century aqueduct column by a post office reminded us that the Romans had been here. In entryways, I found stone stairs rendered concave by boot traffic. Farther up the quai was a former monastery courtyard, overgrown but graceful. In our quartier, there were workshops, not shops: a bookbinder, a violin-repair person, a seamstress, a guitar-maker, a one-room pastry “factory.” The next street over, Arabic was the principal language, and women, their heads covered, fetched water by bucket from an archaic faucet.

There was also—on the nearby Place Sathonay—a porn shop, park benches occupied by drunks, drug deals, graffiti on most surfaces, dog shit everywhere. At a playground, sparkly with bits of broken glass, we watched small children hitting one another. And yet the quartier, for all its in-your-face grittiness, also had energy and integrity and an abundance of small eateries. The food wasn’t grand, but it was always honest, characterized by bon rapport qualité-prix—good quality for the price, an essential feature of the Lyonnais meal. Our apartment was opposite a mural called “La Fresque des Lyonnais,” two millennia of the city’s famous citizens painted onto a six-story windowless wall. The same building housed Bob’s boulangerie, where, friends told us, you could find the best bread in the city.

The boulangerie was where the boys discovered the word goûter (from goût, meaning “flavor,” and probably the single most important word in the entire language). A goûter is an afternoon snack—eaten universally at 4 P.M., when children get out of school—and an exception to two of the city’s implicit rules about food: you do not eat standing up, and you never eat between meals. A goûter is devoured instantly. The boys discovered Bob’s pain au chocolat and didn’t understand why they should eat anything else.

They also discovered Bob’s baguettes, which Frederick developed a practice of assaulting each morning before eating: breaking one open with his hands, sticking his nose inside, inhaling, and then smiling. On Wednesdays, when Bob was closed and we bought baguettes elsewhere, Frederick subjected them to his test and, without fail, found them inedible. (Bob was thrilled by Frederick’s findings.) Bob’s bread had aromatic complexity and was long in flavor in ways that we’d never known before. We were at his boulangerie every day. Some days, we went three times, which concerned him: “You’ve had enough bread today. Go home!”

We had been in Lyon a month when the evidence was inescapable: I couldn’t find a restaurant to take me on. I had cooking experience, but it was mainly Italian, and Italian, I was discovering, didn’t count. I was at home pacing (panicking, frankly), when I declared to Jessica, “I’m going to work for Bob. In fact, I’m going to walk over there now and present myself.”

It was eight in the evening, but I was pretty sure he’d be there. Bob was known for his extreme hours, his light on in the back when the rest of the quartier was dark. And he was there, but he was heading home for a nap.

Bob knew why I was in Lyon. He also knew that I hadn’t found a kitchen to work in. So, when I made my proposal, straight out—“Bob, I’ve decided, on reflection, that I should start with you, in your boulangerie”—he knew that he was my backup: that, in effect, I was lying.

“No,” he said.

“No?” I pressed. “Bob, you make the best bread in the city. I want to learn why.”

His gaze drifted above my head. He seemed to be imagining what it might be like for me to work there.

Bob was forty-four. He was jowly and wide of girth and, when unshaven, looked something like a genetic intermarriage of Fred Flintstone and Jackie Gleason. His hair was brownish and shaggy and usually matted with flour. There was flour in his beard and on his clogs, his sweater, and his trousers. (He wore an apron, but it didn’t help.) Bathing was not a priority. He slept when he could, and seemed to live by an internal clock set to an alarm that was always going off—yeast, dough-making, the unforgiving speed of a hot oven. He knew that his bread was exceptionally good, but he did not see himself as a genius. In a city of food fanatics, he was just a baker. He was, in fact, just Bob. And he wasn’t even that. His real name was Yves. (No one knew why he went by Bob. I once asked him, and he was vague: “Somebody, a long time ago . . .”)