Preheat oven to 325F degrees and place rack in the center positions. Grease a square baking dish (or loaf pan)
In a large bowl mash the banana and mix in the eggs.
Melt butter on medium heat. Remove from heat and mix in brown sugar until melted.
Add butter and sugar mixture along with vanilla to mashed bananas.
Sieve dry ingredients into a separate bowl.
Gently fold dry ingredients into wet ingredients in three parts until just incorporated.
Pour mixture into greased pan and bake for 45 minutes. Do not open over before.
Optional top with cream cheese icing, chill and slice into squares.
