Preheat oven to 350 degrees F.
Grease and flour two 9x13 inch pans.
Use a large mixing bowl and mix flour, sugar, baking powder and salt.
In another large mixing bowl, put together the bananas, egg, melted butter and milk.
Blend the banana mixture into flour mixture until blended but do not over blend.
Stir in chocolate chips and caramel chips.
Split batter equally into both 9x13 inch pans.
Bake at 350 degrees F for 30 to 35 minutes, or comes out clean with a toothpick.
Remove cakes from pan and let both cakes cool completely on a wire rack before icing.
After cakes have cooled, use an offset spatula to layer peanut butter icing (recipe below) on to the bottom layer of the cake.
Clean offset spatula and use it to help guide the other cake layer on top of the bottom layer of cake.
Once cake is set, use offset spatula to layer chocolate icing (recipe below) on to the top and side layers of the cake.