It is written in 'Zoho Shokumotsu Waka Honzo' (an augmented edition of waka poems on food and medicinal herbs) authored by Genrin YAMAOKA in 1723 that broiled eel should be eaten with sansho (Japanese pepper) miso or soy sauce.
1723年に山岡元隣著「増補食物和歌本草」の中に焼いたウナギは山椒味噌や醤油で食べる事を勧める内容が書かれている。