Place slightly damp chicken pieces in a large plastic food storage bag & pound to an uniform thickness. Add 1/3 cup Caesar salad dressing & toss to coat the chicken. Seal bag & place in refrigerator for 1 hour or overnight.
Spread one side each of the 4 bread slices with 1 tbsp each of the Caesar salad dressing. Grill over low flame, dressing side down, 1 to 2 minutes to lightly toast one side of each slice.
Spread remaining Caesar salad dressing, to taste, over each of the 4 untoasted sides of the bread. Sprinkle 3 tbsp of shredded Parmesan evenly over the untoasted sides of 2 slices bread. Set aside.
Grill chicken over medium flame 3-5 minutes per side or until done. Place hot grilled chicken over each of the Parmesan covered bread. Top each with 3 tomato slices, cracked pepper, 4 pieces of halved bacon, & 1/2 cup torn Romaine. Top with 2 remaining bread slices, untoasted sides down. Cut each in half & serve.