Preheat oven to 350 degrees, grease and flour three 8x2 inch round pans. You could use two 9 inch pans it you do not have 8 inch pans.
In a medium bowl, whisk the flour, baking powder, baking soda and salt for 30 seconds, set aside.
In another bowl, add the buttermilk, vanilla and mashed bananas. Blend and set aside.
In the bowl of your mixer, add the slightly softened butter and mix at medium speed until smooth. Gradually add the sugar and continue to mix on medium speed for 3 to 5 minutes until lightened in color and fluffy. Add the eggs one at a time mixing until the yellow of the yolk disappears.
Alternately add the flour mixture and buttermilk mixture, beginning and ending with the dry ingredients (3 additions of dry ingredients and 2 of liquid. Do not mix above medium speed or over mix the batter. After mixing, fold in the chocolate chips.
Pour batter into prepared pans and bake for 25 to 30 minutes. Check at 22 minutes, cake is done with a toothpick comes out clean or with just a few crumbs attached.
Cool in pans 5 to 10 minutes on a cooling rack before turning out.
For the Peanut Butter Frosting
In the bowl of your mixer add the butter and mix on medium speed until the butter is softened and smooth. Add the peanut butter and salt, mix until blended.
Gradually add the powdered sugar alternately with the milk.
Add vanilla and mix on medium speed 4 to 5 minutes until smooth.
Makes 4 ½ to 5 ½ cups depending on the amount of powdered sugar and milk used. It is enough to fill and