Cook the spinach according to the package. Drain the spinach and cool. Set aside. In a fry pan, sauté the onions in the olive oil with basil & oregano until tender. Set aside.
Finely chop artichoke hearts and add to the spinach along with the onions and seasonings. Mix together. Add the cream cheese and sour cream and blend. Add the remaining cheeses except for parmesan cheese.
Spoon into a 13x9 rectangular baking dish. Cover and refrigerate. When ready to serve, sprinkle with the parmesan cheese. Cover and heat in microwave until bubbly hot.