Mix together the salt, pepper and chili powder and set aside.
Cut chicken into similar-sized chunks and then sprinkle with the seasoning mixture.
Mix the remaining ingredients together to make the marinade and either shake it well in a jar or whisk vigorously to emulsify it.
Reserve 3 TBS of the marinade.
Place chicken in a bowl or gallon-sized baggie, and pour the marinade over top. Toss to get it evenly coated. Allow meat to marinate for 30 minutes - 12 hours, tossing occasionally.
When ready to cook, oil your skewers (and clean & oil your grill), skewer your chicken pieces (keeping similar-sized chicken chunks on the same skewers) and grill until chicken is cooked through.
Just before removing from the grill, brush with reserved marinade.
Remove from the grill and serve.
Notes
These skewers are easy to customize. For extra heat, leave the jalapeno seeds in the marinade. Or add in a few dashes of Cayenne pepper to the spice mixture.Tip: Always lightly oil your skewers before sliding meat/veggies on. Metal skewers work best in my opinion.