Chicken Cordon Bleu Casserole

Name: Chicken Cordon Bleu Casserole
Ingredients: Cooking spray; Kosher salt; 8 ounces cooked ham; 3 cups cooked boneless chicken (14 to 16 ounces); 1 (10 1/2-ounce) can condensed cream of chicken soup; 1 cup half-and-half; 2 tablespoons Dijon mustard; 2 teaspoons fresh thyme leaves; 1/2 teaspoon cayenne pepper; 1/4 teaspoon ground black pepper; 1 pound Gruyère cheese, shredded (about 4 cups); 6 ounces dried rotini pasta (about 2 cups); 8 ounces frozen chopped green beans (about 2 cups); 4 tablespoons unsalted butter; 1 cup cornflake cereal