When it comes to sushi, fresh is usually best. Most of the sushi we eat in America is haya-nare, which involves raw seafood and vinegared rice. But in Japan, there's an older form of sushi—said to be the original form—called funazushi. It's made from fermented carp sourced from one particular place, Lake Biwa, and takes about three years to produce from start to finish. The salt it's cured with keeps the bad bacteria at bay, and the result is said to taste like a fish version of prosciutto. Great Big Story recently caught up with Mariko Kitamura, the 18th generation to run her family’s shop in Takashima City, where she's one of the very few people left producing funazushi. You can learn more about the process behind the delicacy, and about Kitamura, in the video below.