Preheat oven to 350 degrees.  Rub a cast iron or oven proof skillet with 1 tablespoon of softened butter.  Open can of refrigerated biscuits and cut each biscuit in half {you will have 16 pieces}.  Roll each half into a ball and place them around the outer edge of the buttered skillet.  In a medium bowl combine the softened cream cheese, mozzarella, pepperoni, mayonnaise, garlic powder and Italian seasoning and mix until well incorporated.  Place mixture in the middle of the skillet and spread out evenly to the edge of the biscuits.  Top mixture with pizza sauce and spread out evenly.  Then top the entire dip and all of the biscuits with the Parmesan cheese.  Bake for 18-20 minutes or until the biscuits are golden brown and the dip is heated through.  Serve warm.