In a medium bowl, combine gochujang, soy sauce, honey, sesame oil, minced garlic, grated ginger, rice vinegar, and black pepper. Whisk until smooth to create the marinade.

Coat the chicken thighs in the marinade, cover, and refrigerate for at least 1 hour or overnight for deeper flavors.

For the slaw, in a large bowl, mix together the cabbage and carrots. In another bowl, whisk mayonnaise, lime juice, and sriracha, then pour over the veggies and mix well.

Heat a grill pan over medium-high. Remove chicken from the marinade and grill for 6-7 minutes on each side until cooked through and internal temperature is 165°F (75°C).

Let the chicken rest for 5 minutes, then slice it into strips.

Toast the buns on the grill pan until golden brown.

Assemble the sandwiches by layering grilled chicken on the bottom bun, top with crispy slaw, cilantro, sesame seeds, and cap with the top bun.