Heat over 400.  Combine flour and butter to make rue.  Stir constantly, whisk in milk and bring to a boil.  Seasonwith salt, pepper and cayenne.  Simmer for 5 to 6 minutes or until rue coats the back of a spoon. Remove from heat and stirin the cheeses,

In a sauce pan heat the  oil, add the onions and saute for 2 minutes, stir in spinach, garlic and artichokes and saute for 2 minutes.  Add salt and cayenne pepper.  Remove from heat and fold into the cheese sauce.  Bake for 10 to 15 minutes or until the top is brown.