Pupusas are to El Salvador what hot dogs are to America, what po-boys are to Louisiana and what burritos are to California. Simply put, they are the national plate of Central America's smallest country, celebrated with a national holiday—and they've been made for the last four years, delicious and cheap, at Pupusas Salvadoreñas in Santa Rosa. But beware: this is a place that turns customers into regulars.

Named after the Pipil, an indigenous group native to El Salvador prior to the Spanish conquest, pupusas, like most south-of-the-border staples, are made from corn. The thick hand-made masa tortillas are filled with cheese, beans, pork, squash, spinach, loroco (a native edible vine flower), or some combination thereof, and then grilled to a golden perfection. Served with salsa and curtido, a spicy cabbage slaw with red chilies and carrots, pupusas are healthier than burgers, more fun than burritos, and, at just two bucks a pop, incredibly easy on the wallet.

Rosa and Antonio Cardona opened Pupusas Salvadoreñas in 2007, despite being "terrified that everything would go wrong." On a recent evening, Rosa's youngest daughter, Seida, agrees to translate, and it's clear from the start that Seida knows the answers to many of the questions for her mother, whose light-filled eyes and easy smile defy her 60 years. Rosa spends every day at the restaurant, and even comes in on Sundays to wash dishes, much to Seida's chagrin. "We all want her to rest," she tells me. But rest is not part of Rosa's pattern.

Pupusas Salvadoreñas' story begins in the 1980s, when Rosa ran a pupusa stand in San Salvador, cooking for hospital staff and patients. But due to the increasing violence and crime that swept the city, she and her husband fled north, followed over the next 10 years by most of their family. Seida was just three years old when her parents left El Salvador, where she continued to live with her aunt and cousins. She did not see her mother again until she moved to Santa Rosa as a teenager, a decade later.

At that time, Rosa was working six days a week, cooking, cleaning and sewing for other people. On the weekends, she made pupusas in her kitchen for friends and family, "just for the heck of it." These social pupusa gatherings grew in numbers and intensity for two years, until, Seida smiles, "it got a little out of hand. They were so popular that cars were blocking the street, and the neighbors were getting mad." So delicious were Rosa's pupusas that people began insisting she accept money for them. Eventually she thought, "Why not open a restaurant?"

The pupusas, which are always made to order, are by far Pupusas Salvadoreñas most popular dish, though other Salvadorian specialties such as empanadas ($1.75), yucca ($7) and sweet corn atole ($2.50) fill the menu, alongside horchata made with morro seeds and peanuts instead of rice ($1.75). "I like only the freshest ingredients," Rosa says. "I'm concerned about health, so the beans are cooked only in oil, never lard." The devotion to quality shows in the restaurant's varied and committed customer base. There are New Zealanders living in Novato who make the trek, and the Santa Rosa Police Department sometimes dines there for lunch. "It's pretty cool when they come," Seida says.

But Rosa could never have predicted their enormous success. "If you work hard, you can have a good job," she says about the United States, and hard work seems to come naturally for the Cardonas. After cooking at a nursing home from 4am to 3pm, Antonio spends his evenings cleaning the restaurant kitchen.

Twenty-year-old Seida juggles SRJC classes with a full-time schedule at the restaurant. And during a major three-month renovation project that started in January, the family closed the restaurant for only one day to tear down a wall, doubling their floor space. "The whole family helped," Seida tells me. "My dad and my uncles can do construction work, so they remodeled the bathrooms and expanded everything."

With fresh flowers in ribbon-tied vases, sprightly music in the background and sparkling clean blond-wood booths and tables, the spiffed-up restaurant invites post-meal lingering. Sporting maps and posters, the walls serve as introductory courses in El Salvador's geography, currency and national treasures. Rosa seems so at home here, in fact, that when asked what she does with her time off, she lets out a chuckle. "I go to church," she says, "but my life is pretty much here."

So does she miss El Salvador? Rosa's gasp needs no translation. "Mucho," she nods, looking right into my eyes. "Mucho. It's very beautiful. When I am too old to work anymore, I want to go back home."

Pupusas Salvadoreñas, 1403 Maple Ave., Santa Rosa. Open daily, 9am-9pm. 707.544.3141.

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