Preheat oven to 375 degrees.
In a medium sized bowl, add cream cheese, mayonnaise, sour cream, mozzarella cheese, gruyere cheese, bacon (reserve some for topping the dip), and combine thoroughly with a spoon.
Pour into a baking dish, cover with foil, and bake for 35 minutes.
Remove from oven. Top with additional bacon and green onions. Serve warm.