Though the restaurants in Little Saigon, run by an older generation of Vietnamese immigrants, don’t tend to veer from traditional fillings, the Phams, when they’re feeling more experimental, color the batter a pale yellow with a pinch of turmeric, or make vegetarian versions with a jackfruit filling, seasoned with soy instead of fish sauce. They’ve also tried gently steaming an egg in the noodle as it cooks, and serving it soft and runny.

At the class t he Phams hosted in their home, students included nurses and food bloggers, pastry chefs and retirees. The couple encouraged them all to steam noodle after noodle, coaching each on technique, and making the case for seeking out the noodle in Little Saigon.

On their way home, a few students stopped by the pots to practice the day’s lessons and make one or two more for the road. Even after a day of steaming and pulling, the noodles were imperfect, and slow to make — a testament to the demanding technique.

Ms. Van and Ms. Lawrence folded the slippery banh cuon directly into their mouths, the noodles somewhat squashed and misshapen, thicker than they should be, but still hot and melting, slick with shallot oil.

They made plans to go out for the noodles next time.

Pho Tau Bay LTT, 3610 West First Street C, Santa Ana

Hong Huong, 8861 Westminster Boulevard, Garden Grove

Banh Cuon Luu Luyen, 14351 Euclid Street 1J, Garden Grove

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