For the chicken soboro (ground chicken sprinkles) see Recipe ID: 1714934, which can be stocked in the freezer.
Put the [A] ingredients in a pan over low-medium heat, and cook it while mixing constantly with 4 to 5 chopsticks held together, until the egg is finely crumbled. Leave to cool.
Put the [B] ingredients in a pan over medium heat, and cook while stirring constantly until there's no liquid left in the pan. Leave to cool.
Put bite-sized portions of sushi rice on lettuce leaves, and top with the toppings of your choice to finish.
Story Behind this Recipe
I had "Sasa-zushi" (sushi on a bamboo leaf) at a friend's house in Nagano prefecture. I can't get large bamboo leaves here, so I used lettuce leaves instead.
For the sushi, besides the chicken, egg and canned mackerel soboro, I used imitation crab sticks mixed with mayonnaise, kimchi, and myoga ginger pickled in ume vinegar. I also serve this with takuan pickles, umeboshi salted plums, stir fried beef seasoned with salt and pepper and so on. You can use whatever you like. ♪