Cook the pasta according to directions, rinse in cold water for a few minutes, then add to a large bowl.
Stir the Caesar dressing into the pasta, until combined.
Add the lettuce and most of the parmesan cheese. Toss to combine.
Sprinkle the remaining parmesan and croutons over the top to serve.
If not serving immediately, cover and chill until ready to serve, then stir in a little more dressing, and top with the remaining parmesan and croutons to serve.
Notes
Storage: Store in an airtight container in the refrigerator for up to 2 days, keeping lettuce, croutons, and reserved parmesan separate if making ahead.