Another simple and yummy twist using basic yellow cake mix...
1 package yellow cake mix
3 very ripe bananas, mashed
1 teaspoon baking soda
1/2 teaspoon cinnamon
oil, eggs, and water, according to package directions
Preheat oven to 350 degrees.
Prepare yellow cake mix according to package directions.
Mash bananas with baking soda and stir into cake mix batter.
Pour into greased and floured 9x13-inch baking pan.
Bake for approximately 40 minutes, or until toothpick inserted in middle comes out clean.