Tet, the Vietnamese Lunar New Year, is a national holiday, not just in Vietnam but all over the world wherever Vietnamese may be. And in the United States, red envelopes filled with money, special dishes and other traditions have become a part of life in major American cities such as San Jose, Houston and especially in Orange County, which is home to the largest Vietnamese expat community in the world.Today, we talk about Tet memories and its evolution with the authors of the recently released “The Red Boat Fish Sauce Cookbook.”More reading:Buy “The Red Boat Fish Sauce Cookbook”A new nuoc mam: Red Boat ‘first press extra virgin’ fish sauceGifts for food lovers: Red Boat fish salt, kids chef caddy, cooking classes