Finely chop the onions and green onions. Grate the nagaimo yams. Mix all of the ingredients except for those marked with ●. Keep kneading and rolling the ingredients around until they all stick together. Let sit for 30 minutes in the fridge.
Add oil to a heated pan, mold the tsukune patties, and cook on both sides.
Once the tsukune patties have cooked through, add in the ingredients marked with ●, and coat the patties. They are finished once the sauce has thickened.
Skewer the patties when transferring to plates, and eat it covered with lots of sauce. Add shichimi spice if you'd like.
Story Behind this Recipe
I wanted to eat juicy tsukune patties, and when I added nagaimo yams, they turned out to be extremely delicious. I used green onions, but Japanese leeks work as well. These don't harden even after they cool, so try frying smaller balls and add to your bento.
At Step 1, thoroughly mix the ingredients for a fluffy texture. When frying in Step 2, the patties are soft and difficult to mold, but it's easier if you mold them into the final shape inside the pan. For those of you that want lots of sauce in Step 3, double the ingredients. In that case, quickly fry the patties, remove from the pan, and cook the sauce.