AI'm new to this and just want to know what others do. If i fill a cake with peanut butter frosting, could i ice the cake with peanut butter frosting? Or do you fill the cake with whatever and always use a buttercream or ganach to ice it.

Just looking for the best icing/frosting to prevent the cake from having bulge or bloating.

Also how stiff should the icing/frosting be. Mine tend to be in the middle (not runny but not hard either) after i do my crumb coat and place it in the fridge for over an hour i apply my fondant and then leave my cake out at room temperature usually 8 hours before the event. I dont use any milk or heavy creams in my frostings.

Thanks :)