Namero

Namerō is a type of tataki, a manner of preparing fish or meat finely minced and mixed with some spices and seasonings, not unlike a tartare. This recipe has been passed down among Bōsō Peninsula fishermen. A dish of grilled namerō is called sangayaki (さんが焼き) or simply sanga. Namerō is grilled directly on an iron griddle, stuffed into scallop or abalone shells or wrapped in sarutoriibara or camellia leaves. Like namerō, it is said to have originated in the Bōsō Peninsula, and there are places specializing in sangayaki.

Source: Wikipedia