First, place 300 g boneless chicken thigh(s) on a chopping board with the underneath facing up (skin-side down) and make horizontal incisions on the thickest parts to make small flaps. Pull out the flaps so that the chicken thigh is more or less an even thickness all the way through.
Flip the chicken over and pierce the skin with a fork all over, then sprinkle with 1 pinch salt on both sides and rub it over.
Dry the surface with kitchen paper and thinly coat the underneath with ½ tbsp potato starch . Make sure to brush off any excess.
Add ½ tbsp cooking oil to a cold pan and place the chicken thigh inside with the skin side facing down. Move the chicken around the pan in a circular motion so that the skin and surface of the pan are evenly coated in oil.
Place the pan on the stove and turn the heat on a medium setting. Fry for 7 minutes, rotating the chicken from time to time to ensure that the skin is evenly browned.
While the chicken is cooking, take a small bowl and add 2 tbsp soy sauce, 2 tbsp mirin, 2 tbsp sake, 2 tsp brown sugar, 2 tbsp dashi stock and 1 tsp honey. Mix until the sugar and honey are dissolved.
After 7 minutes have passed, flip the chicken thigh over and fry for 2 minutes on the other side. Use kitchen paper to wipe up excess oil in the pan.
Once 2 minutes have passed, turn up the heat to medium-high and pour the sauce into the pan. Continuously spoon the sauce over the surface of the chicken until it becomes thick and glossy.
Remove from the heat and rest for a few minutes before cutting it into strips.
Enjoy!