Heat the oven to 350F. Grease 3, 8 inch cake pans.

Puree the banana in a blender till smooth.

In a large bowl whisk all the dry ingredients till thoroughly mixed. In another bowl whisk all the wet ingredients together with the banana puree. Add the dry ingredients and mix until just combined.

Divide the batter evenly between the cake pans. Bake and check for doneness after 30mins or until a toothpick into the middle comes out clean. Allow to cool for 10mins and then transfer to a cooling rack.

Frosting
Whisk the cream cheese, butter and vanilla with electric mixer or whisk for 5mins on medium till light and fluffly.
Turn down to low and slowly add the icing sugar one cup at a time till fully mixed in. Turn up to medium high and beat till light and fluffly.

To assemble
Slice any dooming off the top of the cake layers. Frost a thick layer of frosting over the top of each cake layer and stack on top of each other. Using a palette knife first spread a thinner crumb coat layer of frosting all over the cake and chill in the fridge till firm. Then spread a thick layer of frosting all over the assembled cake.

For how to decorate see above.