Nem (Lao: ສົ້ມໝູ; also spelled som mou), or naem moo, OR naem, literally "sour pork" or "nem pork", is a type of preserved pork sausage that is a traditional celebratory food from Vietnam. It is made from raw ground pork and shredded pork skin. A thin layer of star gooseberry leaves, guava leaves, or fig leaves.. are used to wrap a small lump of raw ground pork and skin. These leaves contains a natural souring agent, causing the raw pork to ferment, making it edible after a few days.