In a large pot, bring salted water to a boil. Add the cavatappi pasta and cook for 8-10 minutes, or until al dente. Reserve 1/3 cup of pasta water, drain pasta, and cool under cold running water.

In a medium bowl, whisk together the pesto sauce, mayonnaise, sour cream, shallot, reserved pasta water, lemon juice, and lemon zest until smooth. Season with salt and pepper to taste.

In a large mixing bowl, toss the cooled pasta with the dressing until well coated. Fold in cherry tomatoes, crispy bacon, arugula, parmesan cheese, and ciliegini mozzarella.

Cover the bowl with plastic wrap and refrigerate for at least 1 hour before serving to allow flavors to meld.