I found this in an the Spring Recipes edition of Orange Page magazine (オレンジページ 春レシピ), a cooking magazine published in Japanese. I was intrigued by the addition of mashed potato to the ingredients list and had to try them. They were delicious and I think they would make good chicken burgers too.
Green Onion Chicken Patties
Orange Page, Spring Recipe Edition p. 23
300g ground chicken
1 large potato (Japan sized – outside of Asia use a medium-small sized potato)
1/2 bunch green onions
1 small egg
2/3 tsp salt
oil for frying
grated daikon radish
Peel, boil (for about 10min) and mash the potato. In a large bowl mix chicken, egg and salt together. When the mashed potato has cooled a bit, add to the meat mixture. Fold in the green onions.
Heat a pan with a tablespoon of oil. Drop large spoonfuls in the pan and fry 3min on each side. Arrange on a plate and put a couple of tablespoons of grated daikon radish on the side. Drizzle the grated daikon with ponzu and serve.