Start by flattening each chicken breast. Place it in a large zip-style bag or between two sheets of plastic wrap. Use a rolling pin or meat tenderizer to gently pound the chicken to an even thickness, about ½ inch. This step ensures even cooking and tender bites.
Add all the marinade ingredients – sweet chili sauce, soy sauce, apple cider vinegar, corn oil, lime juice, garlic, and ginger – into a large zip-style bag. Seal the bag and massage it gently with your hands to mix everything thoroughly.
Place the flattened chicken breasts in the marinade bag, ensuring each piece is well-coated. Press out any excess air, seal tightly, and refrigerate. Allow this to marinate for at least 2 hours, though overnight works best for maximum flavor.
Preheat your grill to medium-high heat. Oil the grates lightly to prevent sticking. Lay the chicken on the grill, cooking each side for about 3–4 minutes. Use tongs to turn the chicken occasionally, basting with leftover marinade for extra flavor. The internal temperature should reach 165°F before you remove it from the grill.
Allow the chicken to rest for 5 minutes after grilling to lock in the juices. Slice and serve with your favorite sides.