Adapted from melskitchencafe.com
cup butter, softened
cup mashed bananas (I use about 3 average sized bananas)
teaspoon baking powder
teaspoon baking soda
Grease and flour 1 large loaf pan (9 1/4 X 5 1/4-inch) or whatever combination of pans you'd like (several commenters have said this recipe works great made into muffins or smaller loaf pans). In a large bowl, cream butter and sugar together. Add eggs, bananas, buttermilk and vanilla until the batter is well mixed. Add in the flour, baking powder, salt and soda. Mix until well combined. Divide batter into greased and floured bread pans and bake at 350 degrees for 50-55 minutes or until a toothpick comes out clean.