“What if a bakery kept its heart and soul, but always remained open to new ideas?” asks the website for Tartine, the world-renowned Bay Area bakery. Elsewhere on the site, the bakery boasts of “Production at a human scale.” Today, the humans who produce Tartine’s award-winning bread and pastries have a new idea of their own: a union.

The workers at four Bay Area locations — three in San Francisco, one in Berkeley — have chosen to become members in the International Longshore and Warehouse Union (ILWU). In doing so, they join their counterparts at another iconic Bay Area institution, Anchor Brewing, one year after Anchor workers went public with their union.

“We’re proud to work at Tartine and want Tartine to be the best it possibly can be,” opens a letter delivered to management Thursday morning by members of the union’s organizing committee. Of the estimated 215 workers at the four locations, 146 signed their name to the letter, a public declaration of their support for the union. The letter requests Tartine voluntarily recognize the union, but notes that should the company refuse, the union will file for a National Labor Relations Board (NLRB) election. Agustin Ramirez, lead ILWU organizer for Northern California, says the union will file for the election on Friday morning, twenty-four hours after the letter’s delivery, should the company decline voluntary recognition.