01 - In a medium bowl, whisk together the Coca-Cola, ketchup, soy sauce, apple cider vinegar, brown sugar, minced garlic, smoked paprika, black pepper, and salt until fully combined and smooth.
02 - Place the chicken breasts in a large resealable plastic bag or shallow dish. Reserve 1/2 cup of the glaze mixture and set aside for basting later. Pour the remaining marinade over the chicken, seal tightly, and refrigerate for at least 1 hour or up to 8 hours for deeper flavor.
03 - Preheat your outdoor grill or grill pan to medium-high heat, approximately 375°F to 400°F. Lightly oil the grill grates to prevent the chicken from sticking.
04 - Remove the chicken from the marinade and discard the used marinade. Place the chicken on the grill and cook for 5 to 6 minutes per side with the lid closed, basting occasionally with the reserved Coca-Cola glaze. Cook until the internal temperature reaches 165°F as measured with a meat thermometer inserted into the thickest part of the breast.
05 - Transfer the chicken to a cutting board and let it rest for 5 minutes to allow the juices to redistribute. Slice if desired, garnish with chopped fresh parsley, and serve immediately.