• In a bowl combine the soy sauce, pineapple juice, honey, ginger, garlic, sesame oil, salt and pepper.
• Place the boneless thighs in a shallow dish or ziploc bag and pour all but ⅓ cup of the chicken marinade over. Reserve the ⅓ cup for basting.
• Marinate for at least an hour or up to 4 hours in the refrigerator.
• Remove the chicken from the marinade, and blot dry.
• Preheat the grill to medium-high heat, about 400°F to 450°F and oil the rack. Turn off one burner if you don’t have an upper rack for indirect cooking. (You will only need this if you have thicker chicken thighs.)
• Place chicken thighs over direct heat on the preheated grill. Cook with the lid closed until it releases easily, about 4 or 5 minutes. Flip, and brush with the reserved sauce. Cook for another 5 minutes.
• Check the temperature. Smaller/thinner chicken thighs may be done at this point.
• If your chicken thighs don’t yet register 165 °F, move to the upper rack or indirect heat, cook until the thickest part reaches there. Remove from heat and rest for 5 minutes before serving.

Ninja Flex Flame:

• Set it to 450°F. Cook 4 minutes on the first side, 3 on the second. The convection fan cooks a little faster, so there's no need to move the chicken to finish, but still check that it hits 165°F.