After its hugely successful exhibit last year on Julia Child, The Smithsonian in Washington, D.C., goes back to the table again with a broader exhibit on food culture called FOOD: Transforming The American Table 1950-2000.

The good news for Dallas: We are represented with artifacts from El Chico and a nod to our most famous invention, the frozen margarita machine.

The 3,800-square-foot exhibit, which opens November 20, has seven parts that hit everything from Teflon and TV dinners to the American wine industry and celebrity chefs. Dallas gets its 15 minutes in a section called the "Mexican Food Revolution," which includes memorabilia provided by the Cuellar family, of the famed El Chico chain, including a stunning sequinned "China Poblana" dress that belonged to Julia Cuellar, wife of El Chico co-founder Frank.

The Smithsonian worked with John Cuellar, one of Julia's five sons, and John's cousin Carmen Cuellar Summers.

"We've been gathering material for over a year," John says. "Smithsonian's curators first came to Dallas to interview Kaleta Doolin, whose father Elmer founded the Frito corn chip in the 1920s. When the curators said they wanted to explore the history of Tex-Mex, Kaleta suggested they contact us."

El Chico's roots date to a taco stand founded by Adelaida Cuellar in Kaufmann County in 1926, giving John and Carmen a wealth of material, which they amassed after El Chico was purchased by Consolidated Restaurant Operations in 1998: historical menus, recipe books, archival photos from when El Chico served Tex-Mex to Princess Grace at the White House and more.

But the curators became especially enamored with a colorful piece of clothing that had historical significance to the Cuellar family: Julia's beautiful sequinned China Poblana skirt.

"When we used to have El Chico restaurant openings, the five Cuellar brothers and their wives would go to the openings and mix and mingle," John says. "The women would wear their sequinned skirts. The China Poblana is the native dress of the state of Puebla in Mexico, usually artfully designed. They became emblematic of Mexican apparel."

After Julia died, John kept her skirt, which has a design reminiscent of the Mexican flag.

"The flag has green, red and white bands and an eagle holding a snake in his mouth. My mother's dress has an eagle holding a snake in its mouth, all in sequins," he says. "We had been keeping it in a Neiman Marcus box since she died in 1990. We wondered, 'What are we going to do with this dress? Nobody is going to want to wear this.' But the curator thought it was really neat and took it back to D.C."

John went back to explore its history more thoroughly.

"The China part of the name is because the Chinese brought silk to Mexico. The blouse of this outfit — it's a blouse and skirt — is silk with silk embroidery on it," he says. "I assumed the whole base of it was cotton. The skirt is cotton, but the blouse is silk. I think that's why the curator was intrigued. When she did a little research, she realized it's probably quite old, because it has the silk blouse."

The Smithsonian is hosting a preview party on Sunday, November 18, and John and his family have been invited to attend.

"My wife Susan, my daughters Catherine and Laura, their husbands — we're all going to Washington," John says. "This is exactly the kind of thing the Smithsonian exhibits want to focus on. Mexican food fits in with their theme and vision and mission. We felt very flattered, and I'm glad I got to talk about our favorite subject."