Bring a large pot of salted water to a boil and cook the cavatappi according to package directions until al dente—this is crucial for the best texture in a cold salad. While the pasta cooks, thinly slice the red onion into half-moons, chop the fresh parsley, zest the lemon, and have your cooked shredded chicken ready. Once the pasta is done, drain it in a colander and transfer to a large mixing bowl while still warm—this helps it absorb the dressing better.

In a separate bowl, whisk together the olive oil, lemon juice, mayo, Italian seasoning, salt, and black pepper until well combined and emulsified. I like to add the mayo to the lemon juice and oil first, whisking it in slowly to create a creamy base before adding the seasonings—this prevents lumps and creates a smoother dressing. Taste and adjust seasoning if needed; the dressing should be bright and balanced with a subtle herbaceous note from the Italian seasoning.

Pour the dressing from Step 2 over the warm pasta in the bowl, then add the chicken, grated parmesan cheese, sliced red onion, arugula, and 0.75 tsp salt. Toss everything together thoroughly to ensure the pasta is evenly coated and all ingredients are well distributed. The warm pasta will help the flavors meld together beautifully as it cools.

Transfer the pasta salad to a serving dish or individual plates. Top with the fresh parsley chopped in Step 1 and the lemon zest, then finish with shaved parmesan if using. I find that adding the fresh parsley and lemon zest at the end keeps them vibrant and ensures the citrus flavor stays prominent—this prevents them from getting lost or wilting into the salad.