So why is XO sauce so special? "Dried scallops are expensive," Lin explains as he checks the temperature of his wok oil. And true, the best XO sauces are made with whole dried scallops, which are harvested from as far as Hokkaido and typically cost over $50 per pound. At the restaurant, Lin and his cooks reserve the extraneous tags pulled from the fresh Maine scallops they serve, and dry them for the sauce. When the dried scallops are steamed, and then fried, it's like eating bacon bits from the sea,, intensely rich, sweet, and salty. They serve as the linchpin in this involved recipe that requires a good amount of time for sourcing ingredients and standing over frothing wok oil.