Preheat the oven to 350°F. Spray a 9-by-5 inch baking pan with nonstick cooking spray.
In a large bowl, combine the flours, sugar, baking soda and salt. In another large bowl, combine the bananas, butter, yogurt, vanilla extract and eggs whisking until smooth. Fold the flour mixture into the butter mixture until well incorporated. Stir in the orange zest and ground cinnamon.
Pour into the prepared pan. Bake until a wooden pick inserted in the center comes out clean, about 50 minutes. Garnish with bananas. Then if you like, spread on a bit of peanut butter, honey or cream cheese.