Bottura, I will learn, has a complicated relationship with grandmothers, whose goddesslike power he both reveres and subverts. This point is illustrated moments later when he stops in the middle of conversation and says, “Oh! Nancy!” Ambling down Via delle Rose is Nancy Silverton, the influential Los Angeles chef, baker and restaurateur, who has a house in Umbria and who frequently drops into Bottura’s restaurant to see what he’s dreamed up. “So good, so good,” says Silverton, thanking him for lunch. Bottura mentions some customers who had expressed a quibble regarding a core component of his “Crunchy Part of the Lasagna.”

“The ragù is not as tasty as my grandmother’s,” he recalls one of them saying. “Can you imagine these guys?” He laughs.“I’m sorry that your grandmother had such bad taste.” This escalates into a comic takedown of grandmothers, with Silverton egging him on. What he’d really like to say to customers who invoke their beloved nonnas is not printable here. In a way, it qualifies as the ne plus ultra in Italian profanity, which is why Bottura would like to have it printed on a T-shirt.

“MODENA IS LITTLE winding streets and unexpected things that happen,” Bottura’s American-born wife, Lara Gilmore, is telling me. It’s a word I’ll hear a lot while I’m there: The unexpected is woven into the ebb and flow round the corner of Via Stella and Via delle Rose.

Consider how Osteria Francescana got its first Michelin star. Bottura opened his restaurant in 1995, and the early days were anxious; customers were scarce and critics were dismissive. In 2001, one of Italy’s most prominent food writers happened to get stuck in bad traffic between Milan and Rome and he stopped in for a meal. A rave review followed and within a year the restaurant had its first star. (It now has three.)

Consider, too, Bottura’s virtuoso improvisations in the kitchen, so rich with the unexpected and the element of surprise. In the same way a jazz musician lets the present moment tell him where he ought to go, Bottura rambles — purposefully — and then reacts. But unlike the Swiss-clockwork kitchen at, say, New York City’s esteemed Eleven Madison Park, where a photograph of Miles Davis looms as inspiration but the room itself remains as silent as a monastery, there is at Osteria Francescana a constant — and conscious — flow of clutter and funk: chefs in loose conversation, Earth, Wind & Fire’s “Boogie Wonderland” blaring from speakers on one side of the alley and the Band’s “The Weight” blaring from the other. “It’s my energy,” Bottura explains. “We cannot live without music, without art.”

Should you visit his home, which he shares with Gilmore and one of their two children (the other is in college), it is a safe bet that he will brandish old 78s of classic jazz — Charlie Parker and Benny Goodman and Billie Holiday. Bottura spent a short time cooking in New York in the early 1990s, and he plays his records on a vintage hand-cranked Victrola that he bought for $150 on the streets of SoHo. “When you are obsessed, really obsessed ...” he says, then trails off.

When Bottura talks about chefs having “a very important sense of responsibility,” he means it. If his cooking is a reflection of what lies inward, his personal mission has been moving in the opposite direction: outward. Revolution is on Bottura’s mind, and not only when it comes to upending the rules of gastronomy. In August, during the Olympics, he opened his Refettorio Gastromotiva in Rio de Janeiro, an ambitious project that involves enlisting talented chefs to turn food waste into delicious and nutritional meals for the poor.