In a medium bowl, whisk together soy sauce, sesame oil, lime juice, garlic powder, ground ginger, and optional chili flakes. Add chicken thighs to the marinade and let them marinate in the refrigerator for at least 20 minutes.

Prepare the peanut sauce by combining peanut butter, soy sauce, honey, rice vinegar, sesame oil, minced garlic, and grated ginger in a mixing bowl. Stir until smooth, adjusting consistency with warm water.

In a large bowl, toss together cabbage, carrots, bell pepper, scallions, and cilantro. Drizzle with lime juice and rice vinegar, mixing well.

Preheat your grill or skillet over medium-high heat. Cook marinated chicken for about 5–7 minutes on each side until cooked through. Allow to rest before slicing thinly.

Warm tortillas in a skillet. Spread peanut sauce on each, add sliced chicken, and top with slaw. Roll tightly and slice in half.

Serve immediately, adding optional garnishes if desired.