Place the soy sauce, 1/2 cup water, garlic, ginger, honey, brown sugar, and sesame oil in a small pot over medium-high heat. Cook for 2 minutes. Turn up the heat to high and bring it to a boil.
Mix the cornstarch with 2 tablespoons of cold water until dissolved. Add the cornstarch mixture to the sauce and boil for 1-2 minutes or until the sauce has thickened. Set sauce aside.
Chicken
Pat chicken thighs dry with paper towels and place them in a large bowl.
Set aside1/3 cup or the teriyaki sauce for later and pour the rest onto the chicken thighs. Mix until the chicken is fully coated.
On the Grill: Heat your grill to medium-high heat (about 400 degrees F). Cook the chicken for 5-7 minutes per sideStovetop Grill Pan: Place the grill pan over medium heat. Cook the chicken for 5-7 minutes per side, working in smaller batches. Wipe out the pan between each batch.
Place the chicken on a cutting board and baste with the reserved sauce. Put the rest of the sauce in a small bowl on the side for dipping. Serve warm with rice and vegetables.
Notes
The teriyaki recipe makes about 1 1/4cups of sauce.