In a mixing bowl, cream butter and sugar.
Beat in eggs, bananas, and vanilla.
Combine the flour, baking soda, and salt.
Add to creamed mixture and mix well.
Pour into a greased 15×10×1 pan.
Bake at 350 degrees for 25 minutes.
Cream butter and cream cheese in a mixing bowl.
Gradually add confectioners’ sugar and vanilla.
Spread over bars.