1. Preheat oven to 350°F Grease and flour 9" x 9" pan.
2. In a large bowl, cream butter and sugar until light.
3. Add eggs and beat well.
4. Dissolve baking soda in sour cream and add to butter mixture, beat well.
5. Reconstitute bananas and add to mix.6. Add cake flour and mix well.
Pour batter into pan and bake at 350°F for 45 minutes or until inserted toothpick comes out clean.
Let cool and serve.