In a large mixing bowl, whisk together soy sauce, banana ketchup, brown sugar, white vinegar, minced garlic, chopped onion, black pepper, salt, paprika, and water until the sugar dissolves completely.

Add the chicken thighs to the bowl with the marinade, ensuring each piece is thoroughly coated. Cover and refrigerate for at least 2 hours or overnight.

Preheat your grill to medium-high heat, aiming for a temperature of approximately 375°F to 400°F.

Take your soaked bamboo skewers and thread the chicken pieces onto them, leaving some space for even cooking.

Place the skewers on the grill, cooking for about 5-7 minutes on each side, applying leftover marinade as it cooks.

Once fully cooked, remove the skewers from the grill and let them rest for at least 5 minutes before serving.