Combine the pasta, pepperoni, cheese, onion, celery, olives and parsley in a large bowl.
Place all of the dressing ingredients in a jar, seal, and shake vigorously to combine. (Alternately, you can whisk together everything but the olive oil, and then gradually drizzle in the olive oil while whisking continuously.)
Pour over enough of the dressing to moisten the salad (you may have a tiny bit leftover) and toss gently to combine. Serve immediately or cover and refrigerate until ready to serve (it's even better after it sits in the fridge, so if you have time to make it ahead, do so!). Leftovers should be stored in the refrigerator for up to 4 days. Splash with additional dressing, olive oil or vinegar if the pasta has soaked up too much moisture on day 2 or beyond.
The ingredients for this salad are highly customizable - add/substitute salami or other Italian meats, add/substitute provolone cheese, omit the black olives if desired (or add green ones!), throw in some artichoke hearts, or anything else you like.
You can easily make this a vegetarian pasta salad by omitting the pepperoni. Feel free to up the other ingredients or add more veggies if you’d like!
My favorite pasta shapes for this salad are medium shells and farfalle, but use your favorite short pasta!
I highly recommend the homemade dressing, but you can totally use store-bought if you’d like. My mom used to put Good Seasons (from the packet!) on her antipasto salads and everyone loved it!
This pasta salad works supremely well made ahead, and can be assembled from a few hours up to a day in advance. Check the salad before serving, as you may need to add a bit more dressing if it’s been in the refrigerator overnight.