Two days before Christmas, a woman was deported after trying to enter the United States at the San Ysidro pedestrian border crossing with twenty-nine pounds of shark fins in her suitcases. (Her cargo, worth some $60,000, violated the Lacey Act, a 1900 anti-poaching law.) Come New Year’s Day with the enactment of AB376 in California, it will be “unlawful for any person to possess, sell, offer for sale, trade, or distribute a shark fin.” Stores and restaurants will have until next January to sell off existing stock, like these fins, priced at $2,200 a pound, which I saw in a San Gabriel Valley apothecary last month.

The bill, co-sponsored by Chinese-American assemblyman Paul Fong, has been controversial: some Chinese-Americans see it as discriminatory, as it targets the key ingredient of a soup traditionally featured at Chinese banquets and weddings. But the practice of finning—removing the fin while at sea and dropping the still-living shark back in the water to drown—is considered cruel, not to mention unsustainable. According to a fact sheet put together by the bill’s proponents, even though current federal law prohibits finning, there is no regulation of the number of sharks killed for their fins—tens of millions every year—and thirty per cent of ocean sharks are threatened with extinction.

For most of 2010, Corey Lee, the former chef de cuisine at The French Laundry, worked on the recipe for a faux shark-fin soup: course sixteen of eighteen on the tasting menu at his acclaimed new restaurant Benu, in San Francisco. He told me that he wanted to challenge himself with a modern interpretation of a classic dish, one he remembers eating as a child in Korea. “The soup is very comforting—very rich and soothing, very savory,” he said.

To prepare his version, which is served (untraditionally) with steamed black truffle custard, he said, “We make a tang—soup with broth—a double bouillon with chicken, Chinese ham, aromatics, and Shaoxing wine.” The “shark fin” texture—he describes it as “gelatinous and brittle at the same, like properly cooked jellyfish”—comes from treating the broth with hydrocolloids, a procedure he arrived at with the help of some food scientists at the San Diego branch of C.P. Kelco, a major producer of culinary and household gums. “The research involved having real shark fin, so they could have a reference point,” he said. “I prepared it and sent it down.”

The greatest compliment Lee has received so far came from Cecelia Chiang, the revered chef and restaurateur who is credited with introducing Northern Chinese cooking to America. “She had no idea it was faux,” he said. (Alice Waters, a friend of Chiang, said in 2009 that she hoped her last meal would be shark-fin soup prepared by Chiang; not long afterward, she signed a Humane Society pledge renouncing shark fins forever.) Chiang, Lee said, has come back many times.

Alice Waters is not the only prominent convert to the cause. Yao Ming, the former N.B.A star and in his youth a player for the Shanghai Sharks, filmed a public-service announcement exhorting Chinese diners to reject shark-fin soup. Not long ago, Lee said, Ming had stopped by Benu to try some of the fake stuff, but left disappointed. “He came, but we had a private party so we couldn’t seat him!” Lee said.