Spray a 9x5 inch loaf pan with cooking spray.
In a large bowl, combine flour, baking soda and salt.
In a separate bowl, cream butter and brown sugar. Stir in eggs and mashed bananas until well blended.
Stir banana mixture into flour mixture, stir just to moisten.
Pour batter into pan.
Bake for 60-65 minutes until a toothpick or knife inserted into the center of the loaf comes out clean.
Let bread cool in the pan for 10 minutes before removing and slicing.