If using wood skewers, make sure to soak them in water before using.
Combine all ingredients for BBQ sauce in a bowl and whisk well.
Cut excess fat off chicken thigh meat and cut chicken thighs into 3 or 4 equal pieces.
Place chicken in a gallon zip-lock bag and add BBQ sauce to it. Close the bag and gently shake it to make sure all the chicken pieces are evenly coated in BBQ sauce. Let chicken marinade while preparing coals.
Prepare coals and preheat the grill. Make sure the rack is clean.
Skewer chicken pieces onto the skewers, dividing chicken equally among the 6 skewers. You will be able to get 6-7 pieces of chicken per skewer.
Save remaining marinade and place it into a small metal cooking dish. Cook it along side of the chicken. (You can also cook the BBQ sauce on the stove-top if you wish.) Just make sure to bring it to simmer and cook for a couple of minutes. You may not see it simmer on the grill so use a thermometer to bring it to a temperature of 165 degrees.
Turn chicken skewers a quarter of the way around every 4-5 minutes while cooking. (Depending on the size of your chicken pieces, it may take a little more or a little less time to cook though.)