click to enlarge Chris Duffey/File photo

The signature dish.

Sad news for fans of hard-to-find Vietnamese noodle soups: Bun Mam Soc Trang (1326 E. 18th St., Oakland), which, for my money, was the best Vietnamese restaurant in Oakland, has closed.When reached by phone, co-owner Hien Tran, who ran the popular noodle shop along with her mother Dieu Tran, said Bun Mam Soc Trang’s last day of business was December 21. Tran’s initial plan had been to take a brief year-end vacation — but then, without warning, her landlord delivered the unexpected news that the restaurant’s lease wouldn’t be renewed when it expired at the end of January. According to Tran, the landlord said the restaurant attracted too many customers for such a small space. Regardless, the Trans ultimately decided it wouldn’t make sense to reopen for only a few weeks.The restaurant's signature dish was, of course, its, a soup whose characteristic tang came from the use of fermented mudfish. But the other home-style regional noodle soups — especially the crab-infused— were just as notable.Tran hopes to eventually reopen at a different East Bay location, but she said that, like many small business owners, she has found the current commercial real estate market to be daunting. In the meantime, customers can visit this placeholder website for updates.