I found some really good @mackerel at the local mart before I left work and went home.
I remembered what a YouTuber said below and bought the @mackerel.
"Fresh@mackerel sold at the mart is delicious even when pickled."
After cutting the mackerel into 3 pieces, marinate it in coarse salt for 30 minutes, wash it well in running water, and marinate it again in vinegar water for 40-50 minutes.
I was going to eat it right away in the evening, so I marinated it briefly in salt and vinegar water and removed the ribs and small bones from the fish flesh that were left.
I made sushi rice, put it in @mackerel with wasabi and green onions, rolled it up well, and then torched it.
Grate the ginger you purchased together and place it on top to complete “Shimesaba Bouzushi.”