Preheat the oven to 350 degrees F. Coat a 12-cup muffin tin with nonstick cooking spray. In a large bowl, beat the butter and sugar until creamy. Add the eggs and beat until light and fluffy. Stir in the bananas; mix well. Add the flour and baking soda, stirring just enough to moisten. Spoon the batter into the muffin cups and bake for 25 to 30 minutes, or until a wooden toothpick inserted in the center comes out clean.
baking, or toss some chocolate chips and/or chopped nuts into the batter.