01 - In a medium mixing bowl, combine the Coca Cola, ketchup, soy sauce, apple cider vinegar, brown sugar, minced garlic, smoked paprika, black pepper, and salt. Whisk thoroughly until all ingredients are fully blended and the sugar has dissolved.
02 - Place the chicken breasts in a large resealable plastic bag or shallow dish. Reserve 1/2 cup of the marinade mixture for basting during grilling, then pour the remaining marinade over the chicken. Seal the bag or cover the dish and refrigerate for at least 1 hour, or up to 8 hours for deeper flavor penetration.
03 - Preheat your outdoor grill or grill pan to medium-high heat, approximately 375°F to 400°F. Lightly oil the grill grates using a folded paper towel dipped in vegetable oil to prevent the chicken from sticking.
04 - Remove the chicken breasts from the marinade, allowing any excess to drip off, and discard the used marinade. Place the chicken on the preheated grill and cook for 5 to 6 minutes per side with the lid closed. Baste occasionally with the reserved Coca Cola glaze during the final minutes of cooking. Continue grilling until the internal temperature reaches 165°F when measured at the thickest part with a meat thermometer.
05 - Transfer the grilled chicken to a cutting board or platter and let it rest for 5 minutes to allow the juices to redistribute. Garnish with chopped fresh parsley if desired, then serve alongside grilled vegetables, corn on the cob, or a light summer salad.