Preheat the oven to 350 degrees. Spray a 9 by 13 inch baking dish with cooking spray and set aside.
Bring a large pot of water to a boil. Season the water with 1 teaspoon of salt. Add the egg noodles and cook according to package instrucitons.
While the noodles are cooking, melt butter in a large skillet. Add the mushrooms and saute until they are soft, about 4 to 6 minutes.
Whisk in the flour and then very slowly whisk in the chicken stock. Add just a few tablespoons at a time, whisking to combine it, until it is completely added.
Whisk in the milk, garlic powder, onion powder, salt and pepper.
Bring to a simmer, and then cook, stirring often, over low heat for 5 minutes. Stir in the sour cream and 1 cup mozzarella, taste and add more salt and pepper if needed.
Add noodles and diced turkey to the prepared baking dish. Stir in the sauce. Top with remaining mozzarella and Parmesan cheese. Cover and bake for 30 minutes.