Chicken Delight

2 1/2 to 3 cups cooked chicken, cut into bite size pieces
2 cups cooked wide egg noodles
2 Tbsp butter
1/4 cup chopped onion
1/4 cup chopped bell pepper
1 can cream of mushroom soup
1 cup sour cream
1/4 cup milk
1 cup shredded cheddar cheese

Brown onion and bell pepper in butter. Combine all ingredients except parsley flakes and cheese. Spray 13x9 pan with nonstick spray. Pour casserole mixture into dish. Top with parsley and cheese. Bake at 350 for about 30 minutes.