Turkey Tetrazzini

Ingredients:
1 can mushroom
1/2 cup flour
2 cups chicken stock
1/4 teaspoon black pepper
3 tablespoons butter
1 small onion -- diced fine
1 rib celery -- diced fine
2 cups cooked spaghetti
2 cups cooked turkey -- chopped
1 tablespoon pimiento
3/4 cup Parmesan cheese
1/4 teaspoon poultry seasoning
3/4 cup milk
1 tablespoon onion powder
1 teaspoon minced garlic
shredded cheddar cheese, to taste
parsley, to taste
salt to taste

Instructions:
In a large pot melt the butter and saute the onions, garlic and celery.
Once onions and celery turn translucent stir in the flour.
Stir in the chicken stock to make a medium veloute sauce. (A veloute sauce is a sauce made by using roux and chicken stock.)
Once the sauce reaches a medium thickness stir in the milk then add the remaining ingredients, except for the cheddar cheese.
Spray a casserole dish with non-stick cooking spray, then add mixture into the dish.
Place the dish into a 350 degree oven until casserole starts to bubble, then remove from oven and top with the cheddar cheese.
Place the dish back into the oven and bake until cheese is melted.
Remove dish from the oven and let rest for 10 minutes.
Serve.