Mix the cream cheese, sour cream, mayonnaise, 1/2 cup of mozzarella, and 1/4 cup of parmesan in a large mixing bowl. Transfer the mixture to a pie plate and spread it into an even layer.
Spread the pizza sauce over the top of the dip. Then sprinkle the remaining mozzarella and parmesan on top. Arrange mini pepperoni slices and olives all over the cheese, using as much as you like.
Bake for 20 minutes or until the sides are bubbling and the cheese has melted and turned golden brown on top.
Remove from the oven and let rest for 5-10 minutes before serving with baguette slices.