BARS:
In a small saucepan over medium to medium-high heat, bring butter and water to a boil.
Remove from heat; set aside.
In a small measuring cup, measure buttermilk or soured milk.
Stir in baking soda; set aside.
In a large mixing bowl, beat the sugars, bananas, buttermilk or soured milk, eggs and vanilla until well blended and smooth.
Add flour to sugar mixture.
Carefully beat in butter mixture until blended.
Stir in chopped walnuts or pecans.
Pour mixture into a greased 10x15” cookie sheet pan.
Bake at 350º for 18-22 minutes, or until a toothpick inserted in center of the pan comes out clean.
Cool bars in pan on wire rack.