There may be no burrito as beloved in San Francisco — or as famous throughout the country — as the one from La Taqueria, the Jara family’s 45-year-old restaurant on Mission and 25th streets. Known as La Taq, it has made regular appearances on The Chronicle’s annual Top 100 restaurants lists, and in 2017, the James Beard Foundation honored it with an America’s Classic designation.

Owner Miguel Jara, 75, has often spoken to the media about how much he values his workers, several of whom have cooked at La Taqueria for more than a quarter-century. Yet in November, San Francisco’s Office of Labor Standards Enforcement and the California Labor Commissioner fined La Taqueria for numerous labor violations, including unpaid overtime, sick pay and health care costs.

Four La Taqueria workers filed the complaints after several years of planning. Soon after, Jara, who runs the restaurant with his sons Angel and Jesus, paid nearly $500,000 in unpaid wages and penalties, and made changes to restaurant operations. Then, the Jaras fired the organizers, an act that in turn sparked a new round of retaliation complaints that were settled last week — for an additional $100,000.

“We’ve been in business with this family for 45 years,” Angel Jara said. “It’s such a black eye and so upsetting.”

What happened at La Taqueria exemplifies the violations that regularly occur in small family-owned restaurants: informal arrangements that turn out to be illegal, ignorance of labor laws on the employer’s end, and immigrant workers afraid to advocate for themselves in the workplace.

What makes the case unique, perhaps, is that the four women who spoke out educated themselves about their legal rights — and then acted to extend these rights to all their co-workers.

Compact and soft-spoken, with hair pulled into a precise, round bun, Cristina started at La Taqueria in 2008, two years after moving to San Francisco from Guanajuato, Mexico.

(Cristina is a pseudonym. Cristina, Jessica and Angela, interviewed over the course of this months-long Chronicle investigation, requested their last names not be used for fear of endangering their current employment. Angela and the fourth woman involved in the case, Victoria Romero, were involved in the original complaints but not the retaliation case.)

Cristina liked the work — a bit of everything, from food prep to running the cash register. “It was constant,” she said, speaking through a translator. “It was a little tiring when a lot of people came through.”

Even after nine years, Cristina was one of the junior employees. So was her co-worker Jessica, who had been there eight. Of the 28 employees whose work hours were later tracked by the city investigation, 14 had worked at the taqueria longer than a decade, one as long as 35 years. All, Angel Jara said, make more than minimum wage; some as much as $25 an hour. Six employees live in apartments the Jaras own. “There must be a reason why they stay around with me,” his father said.

The pace of Cristina and Jessica’s work intensified after September 2014, when news website FiveThirtyEight named La Taqueria’s carnitas burrito the best in America. The restaurant had been bustling for decades, but the lunch line had never before extended to the end of the block. Angel Jara estimated that business tripled, with the same staff.

Neither woman had worked in restaurants before, so they accepted many of the policies that La Taqueria management had instituted.

Their schedule made sense from a purely mathematical perspective: four 10-hour shifts a week. The Jaras say they established that schedule 13 years ago, with the consent of the workers, and if employees stayed a few minutes after hours to clean up, they’d occasionally get an extra $20 or so to compensate.

La Taqueria’s tipping system was, Cristina said, “a little complicated.” The Jaras maintained a list of employees, and each day the contents of the tip jar would go to the next person on the rotation. Roughly once a month, one worker would receive $300 to $500, depending on the day’s take. New workers received nothing until they had been employed for six months.

Cristina and Jessica alleged that Jara, his sons and the manager all shared in the tip distribution, which would be illegal under federal and state labor laws. Angel Jara, who confirmed the tipping arrangement, acknowledged that he was part of the rotation when he was, in his words, a regular hourly worker, and stopped when he stepped up as vice president.

It took the firing of Victoria Romero and Angela in the fall of 2016 to spur the workers to ask for changes. Both employees had worked at the restaurant a year or less. Angela was dismissed for, in her words, “not showing respect” to the manager — which the Jaras both confirm. Romero said she was let go for taking a break to run to an interview.

The two say they disputed the terms of their dismissal and wanted to share their experiences of the labor violations they observed. They made their way to Young Workers United, a 16-year-old San Francisco organization that helps low-wage workers, particularly Spanish-speaking ones in the service industry, with wage theft and discrimination on the job.

According to representatives from Young Workers United and the Asian Law Caucus, the two organizations that assisted with the La Taqueria case, most workers approach them with individual claims. Once Angela and Victoria learned how many rights they were denied at La Taqueria, however, they wanted to organize the employees at their former workplace.

Angela called up the former co-workers she had been closest to. When she explained her complaint to Cristina and Jessica, who still worked at the restaurant, both were surprised — particularly about the fact that they had the legal right to take sick time to care for themselves or their children. “I felt bad, and frustrated and angry realizing that I had a right that I didn’t know about for so long,” Cristina said.

From Young Workers United, the women learned that according to California state law, employees in nonmanagerial positions who work more than eight hours in a day must be paid 1.5 times the hourly wage for extra hours, and employees cannot legally waive their right to overtime.

They also learned that current San Francisco law requires all employers to bank one hour of sick time for every 30 hours an employee works, though businesses can impose a maximum of 40 or 72 hours of paid leave per year, depending on the employer’s size. The women could use those days not only for themselves, but to care for their children.

In addition, the four women discovered they were entitled to thousands of dollars each year to spend on their family’s health care. San Francisco’s Health Care Security Ordinance requires all businesses with more than 20 employees to set aside a certain amount per employee per hour — the current minimum is $1.89 — toward health care, either in the form of insurance or a health care savings plan.

All of these rights were explained in a poster that employers are required to display, but at the restaurant, they said, no one could read it, because it was written in English and taped up too high.

“The La Taqueria situation is all too common. We see that especially with a changing workforce in San Francisco,” said Ilana Master, campaign manager at Young Workers United. “Workers are seen as disposable. The restaurant industry is an unregulated industry. There’s so much ability to create wage theft and sexual harassment without coming under attack.”

A 2017 report from the Economic Policy Institute, for instance, estimated that 4.1 percent of California workers experienced wage theft in 2011. That figure rose to 19 percent when applied to low-wage workers, and noncitizens making minimum wage were 50 percent more likely to experience wage theft than U.S. citizens. In a 2010 study of 433 restaurant workers in San Francisco’s Chinatown, 76 percent of workers reported that they were not paid overtime, and half reported minimum wage violations.

“Unfortunately, failure to pay overtime and provide accurate itemized statements are very common violations in the restaurant industry,” Jeanne-Mairie Duval, spokeswoman for the California Labor Commissioner’s Office, wrote in an email.

In October 2016, former employees Angela and Victoria, along with representatives from Young Workers United and the Asian Law Caucus, inaugurated a series of meetings with the Jaras. As the meetings progressed, current employees Cristina and Jessica joined in, exposing their involvement in the complaints.

The Jaras did make several changes to make their informal employment practices legal. In February 2017, the restaurant owner filed paperwork with the state labor commissioner to have an alternative workweek of four 10-hour days — a process that required the staff to have a silent vote on the schedule. The Jaras reinstalled a time clock and began issuing checks calculating paid sick leave, a shortcoming that Angel Jara attributed to the restaurant’s accountant.

But, Cristina and Jessica said, he didn’t resolve their other concerns about health care costs, the tip system and the treatment of lower-seniority workers like them.

For all their attempts to be discreet, they said, the atmosphere at La Taqueria grew tense. According to both sides, Miguel Jara stopped coming into the restaurant, too disturbed by the complaints.

Aided by the Asian Law Caucus, the four past and present employees finally filed formal complaints last summer, and both the city and state began investigations.

On Nov. 13, the California labor commissioner’s Bureau of Field Enforcement issued the first citation: $140,291 in unpaid overtime, plus $86,400 in civil penalties for both unpaid overtime and lack of itemized wage statements on their paychecks, going back three years.

Nine days later, the San Francisco Office of Labor Standards Enforcement issued another violation: $207,181 to employees for unpaid health care expenses, plus $28,698 to the city in penalties.

According to Pat Mulligan, director of San Francisco’s Labor Standards Enforcement, his office investigates 60 to 90 complaints a year similar to the one against La Taqueria. Three-fourths result in fines and penalties, ranging from $50 to $4 million, currently averaging $130,000 to $140,000.

Miguel Jara says his accountant had misinformed him that the Health Care Security Ordinance applied only to businesses with 50 employees or more, almost twice the number at La Taqueria. He sold a property and made other arrangements to pay the fines.

“In this case, the employer was very responsive,” Mulligan said. La Taqueria didn’t appeal either citation. In fact, Jara issued checks to current and past employees so quickly, passing them to the Office of Labor Standards Enforcement to distribute, that the city office waived its penalty fees.

Within a few days after the last checks were distributed, just before the restaurant closed for its three-week holiday break, the Jaras called their 26 employees together in a public meeting and fired seven workers. Among them were Cristina and Jessica.

“The numbers showed we could make the same amount of money. Because you have to let seven people go, between the salaries and the insurance, we make more money by closing two days a week instead of one,” Miguel Jara said.

Angel Jara said the decision was not made to make La Taqueria exempt from the Health Care Security Ordinance. The business continues to contribute to the city’s health care savings program for the remaining workers, he said.

The Jaras dispute that laying off Cristina and Jessica was retaliatory. “If there was no lawsuit, they would have been let go anyway,” Angel Jara said, complaining about their tardiness to work, their performance on the job and their attitude.

Cristina, Jessica and a third unnamed co-worker (a friend of the women, also released) quickly filed retaliation complaints with the state Bureau of Field Investigation. Negotiating a second state-mediated settlement took another six months. Although the Jaras still deny they are at fault, last week, according to Asian Law Caucus representatives, Jara settled the lawsuit and paid the three fired workers almost $100,000 in lost wages and penalties.

According to Winifred Kao, litigation director for the Asian Law Caucus, the payment wasn’t the only part of the settlement. Jara agreed to post a Spanish-language announcement in the workplace — explaining workplace rights, including protections against retaliation — and to hold trainings on the laws La Taqueria was cited for violating.

“That settlement is a powerful one,” Kao said.

Though the topic of the dismissal is still painful, Cristina is unwilling to speak ill of Jara or La Taqueria. She misses the food. At the same time, she feels a sense of satisfaction with what she achieved. “We were successful because the people who are there now are receiving benefits. My co-workers who stayed have come and told me, ‘Oh, do you know I’m getting sick leave?’” she said. “It makes me happy to know that we did what we did.”

Victoria Romero, who is in her sophomore year at San Francisco State University, says that their success has inspired her to continue her studies in criminal justice. “We have rights, and we’re human. It doesn’t matter what kind of person you are, if you have a problem you don’t stay quiet. You speak up.”

Chronicle staff writer Esther Mobley contributed reporting and translation assistance to this report.

Jonathan Kauffman is a San Francisco Chronicle staff writer. Email: jkauffman@sfchronicle.com Twitter: @jonkauffman