The story of stone soup may be a classic childhood tale, but another dish, caldo de piedra, in the Mexican state of Oaxaca is another story altogether.

It's a soup that goes back to pre-Hispanic times in the Chinantla region, which borders Veracruz.

“It's basically a dish cooked by men to honor women,” said Geronimo Lopez-Monascal, executive chef at Nao, the restaurant at the Culinary Institute of America, San Antonio, which serves a refined version of the traditional soup. “That's why it's so simple.”

It's part of an indigenous daylong springtime celebration when women aren't supposed to cook or do any work. The men make the soup, and it is the meal for the day.

In perhaps the most traditional version of the soup, men dug a pit in the sand of a riverbank and lined it with large, edible leaves before adding chiles, vegetables and water. Then they added rocks that had been heated directly on an open fire. When the water began bubbling, the men would add freshly caught seafood from the river. All this was then served in hollowed-out gourds.

In her seminal “Oaxaca al Gusto,” Diana Kennedy described watching a small home-based restaurant add hot rocks to individual gourds filled with native shrimp, chopped tomato, onion, green chile and epazote.

“As the water bubbled furiously, a column of steam hissed upward like a geyser,” she wrote. “When the bubbling died down, the stones were removed and, believe it or not, the ingredients were cooked.”

When it came time to design the menu for Nao, Lopez-Monascal and the other chef-instructors at the CIA wanted to feature dishes that diners here likely didn't know. The Oaxacan classic was a natural.

“We wanted to feature Latin cuisine that was traditional and beautiful and could be worked into a modern presentation without compromising quality or taste,” Lopez said. “This has a very showy presentation, but it's comfort food. It's caldo.”

The restaurant version refines the tradition by clarifying the broth, cooking the shrimp sous vide and adding finely julienned tortilla strips. In early restaurant run-throughs, the restaurant staff learned to have servers use a napkin to protect diners from splatters when the broth hits the hot rocks.

Now, a new class of associate degree students is about to start and the second class of the Latin cuisines certificate program begins in March. Expect to see the hot-rock technique in other dishes as the restaurant evolves.

“We want to re-create the style of service and the visuals that you will find, not only in Mexico, but in Peru and Venezuela,” Lopez-Monascal said. “People can see how we do things so they can imagine a little bit, travel a little bit.”