Preheat the oven to 375°F. Spray a 9×13 casserole dish with nonstick cooking spray. Set aside.
Cook the cavatappi pasta in a large pot of boiling water, according to package directions, for 7 to 8 minutes or until the pasta is al dente.
In a large bowl, stir together the cream of chicken soup, half & half, Dijon mustard, fresh chopped parsley, season salt, and black pepper.
Add the shredded Swiss cheese, diced rotisserie chicken, and cooked cavatappi pasta. Stir to incorporate all the ingredients fully.
Pour the chicken cordon bleu casserole filling into the prepared casserole dish.
In a small bowl, stir together the melted butter, plain panko bread crumbs, and grated parmesan cheese.
Cover the top of the casserole filling evenly with the panko breadcrumbs.
Bake for 25 to 30 minutes or until golden and bubbly.