In a medium bowl, combine the soy sauce, brown sugar, fish sauce, peanut butter, sesame oil, coriander, cumin and garlic powder. Whisk together until combined.
Add the chicken cubes to the marinade and stir to coat. Cover and refrigerate for at least 30 minutes.
Preheat an outdoor grill or indoor grill pan to medium-high heat.
Thread the chicken cubes onto 8 skewers and brush lightly with oil.
Grill the skewers for 5-7 minutes per side or until cooked through.