In a large bowl, add barbecue sauce, oil, garlic powder, smoked paprika, salt, pepper and whisk. Add chicken breasts, stir with tongs to coat and let marinate for 30 minutes to up to 24 hours.
Preheat your grill on medium-high heat, 450F – 500F. Rub grill gates with oiled paper towel then add chicken. Brush each breast with BBQ sauce and grill for 5 minutes with lid closed.
Open the lid, brush the same side with more BBQ sauce. Then flip and brush with sauce again. Close and cook for another 5 minutes or until internal thermometer reads 165 F at the thickest part of the breast.
Refrigerate in an airtight container for up to 5 days. To freeze, freeze whole chicken breasts to retain maximum moisture in an airtight container for up to 3 months.