Preheat oven to 350°F. Coat a 13x9-inch baking dish with nonstick spray, or prep a 12-inch skillet.
Cook Chicken Breast, or strip a rotisserie chicken. Shred tender meat with 2 large forks, or with a stand or an electric mixer.
Bring a large pot of salted water to boil over medium-high heat. Add egg noodles and cook al dente, about 7 minutes. Drain and set aside.
In a large bowl, add cream of chicken soup, milk, cheese, chicken bouillon, salt, and pepper, and stir together.
Stir in shredded chicken, onion, celery, and thawed frozen vegetables.
Fold in the cooked egg noodles. Spoon mixture into baking dish and spread evenly.
Stir together Ritz cracker crumbs and Butter in a small bowl. Sprinkle mixture evenly overt he casserole. Bake approx. 25-35 minutes, until topping is lightly browned.
Let set for 10 minutes. Sprinkle with sliced green onions and parsley. Serve and enjoy!