Preheat oven to 350F degrees. Spray 9x13-inch baking dish with non-stick cooking spray.
In a large bowl, combine chicken, cream of chicken soup, mayonnaise, milk, diced onion, shredded cheese and frozen peas and carrots. Stir until combined.
Gently stir in cooked egg noodles.
Pour in baking dish. Sprinkle top with bread crumbs.
Pour melted butter evenly over top of bread crumbs.
Bake uncovered for about 30-35 minutes until bubbly and top is golden brown.
