In a large mixing bowl, whisk together the melted unsalted butter, minced garlic, smoked paprika, onion powder, chili powder, ground cumin, salt, and black pepper until well combined.

Add the boneless, skinless chicken thighs to the bowl, tossing them well in the marinade to ensure every piece is thoroughly coated. Cover the bowl with plastic wrap and refrigerate for at least 30 minutes.

Preheat your grill to medium-high heat, around 400°F (205°C). If using wooden skewers, soak them in water for 30 minutes.

Remove the chicken from the fridge and thread the pieces onto the soaked skewers, leaving a little space between each piece.

Carefully place the skewers on the preheated grill and cook for about 4-5 minutes on each side until the internal temperature reaches 165°F (75°C).

Once cooked, remove the skewers from the grill and brush them with any remaining melted butter. Garnish with freshly chopped parsley and serve warm.