In a large bowl, combine the pasta, bacon, tomatoes, and Caesar dressing; mix until well-combined. Gently stir in the cubed avocado. Serve immediately by placing chopped romaine lettuce on a plate and then topping with pasta salad. Sprinkle with grated Parmesan, if desired.
You may use your favorite shape of pasta in this recipe, such as bowtie (farfalle), corkscrew (fusilli), or macaroni, although I would recommend sticking with a pasta that's not too large and not too small. I happened to find trottole at my grocery store, which I thought was a fun and different shape for this pasta salad.
This is a good pasta salad to prepare and serve immediately, so that the pasta and bacon are still slightly warm in contrast to the cool tomatoes, avocado, and lettuce. Alternatively, you may combine the pasta, bacon, tomatoes, and dressing ahead of time and refrigerate. Then just before serving, mix in the avocado and, if needed, a bit of additional Caesar dressing (to compensate for the dressing that gets absorbed while chilling).