Trim any excess fat from chicken. Place a piece of plastic or parchment on top of each chicken breast on a solid, level surface, and pound the thick end of chicken to flatten to an even thickness.

Place chicken in a large resealable plastic bag. Add olive oil, Dijon, honey, soy sauce, lemon juice, garlic, onion powder, and ginger to the bag. Press any excess air out of the bag and seal the bag tightly. Massage chicken around in the bag until marinade is fully incorporated and chicken is well coated. Refrigerate for at least 4 hours or overnight, turning the bag occasionally.

Preheat an outdoor grill for high heat, about 400 degrees F (200 degrees C). Brush the grill grates with oil or coat with cooking spray.

Place chicken, top side down, on the grill. Sprinkle evenly with salt. Cook, undisturbed, until chicken easily releases from the grill and has dark brown grill marks, about 3 minutes. Reduce heat to 350 degrees F (175 degrees C) or medium heat, then flip and cook an additional 5 to 7 minutes or until chicken has reached an internal temperature of 165 degrees F (73 degrees C). Remove from heat and let stand 5 to 10 minutes before serving.