Preheat oven to 375°F and lightly grease your baking dish.
In a large bowl, mix together cream cheese, mayonnaise, sour cream, Parmesan, Worcestershire, paprika, garlic powder, oregano, black pepper, and cayenne until smooth. Fold in the chopped onion.
Spread the mixture evenly into baking dish. Sprinkle the fried onions evenly on top.
Bake for 20–25 minutes, until bubbly and golden at the edges.
