Talking of sushi (I adore sushi), Number 2 husband was a chef at a top hotel in London, and he used to make us these ground beef and pork meatballs in a crisp coating with Tonkatsu sauce and they are divine. I couldn’t remember their name so I just did a search and apparently they’re called Menchi Katsu and are more ‘Western-Japanese’ that traditional Japanese.
I definitely recommend them.
https://www.justonecookbook.com/menchi-katsu/
The tonkatsu sauce came in a bottle, but I’ve never seen any outside London. There are some recipes for home-made on the interwebs, though.