In a large stock pan, form a roux by whisking together melted butter and flour. Slowly whisk in stock, milk, parmesan and seasonings and simmer until thickened.
To the cream sauce, add in cooked noodles and shredded chicken and stir to combine.
Spread Casserole out into a greased baking dish and top with additional freshly grated Parmesan cheese.
Bake the chicken casserole at 350 degrees Fahrenheit for 20-25 minutes until warmed through and the cheese is golden.