01 - 
                Place chicken thighs in a bowl and pour over the soy sauce and mirin. Mix well to coat evenly, then cover and marinate in the fridge overnight.
              
              
              
                02 - 
                Combine all the sauce ingredients in a small saucepan. Simmer gently for 5 to 10 minutes, stirring occasionally, until it reduces by half and thickens slightly. Set aside to cool.
              
              
              
                03 - 
                Place the chicken thighs skin-side up in a single layer in the air fryer basket. Cook at 350°F for 10 minutes.
              
              
              
                04 - 
                Turn the chicken over so the skin side is down. Continue cooking at 350°F for another 5 minutes, or until the internal temperature hits 165°F.
              
              
              
                05 - 
                Brush the bottom of each chicken thigh with teriyaki sauce, then flip and brush the skin side as well. Air fry again at 325°F for 3–5 minutes, just until the sauce thickens and gets sticky. Watch closely to prevent burning.
              
              
              
                06 - 
                Let the chicken rest for 5 to 10 minutes before slicing. Serve warm with steamed rice or your favorite sides.