Ingredients

• 1/2 cup shortening
• 1/2 cup butter, softened
• 1 cup white sugar
• 2 eggs
• 1 cup mashed bananas
• 1/2 cup evaporated milk
• 1 teaspoon vanilla extract
• 1 teaspoon distilled white vinegar
• 3 cups all-purpose flour
• 1 1/2 teaspoons baking soda
• 1/2 teaspoon salt
• 1 cup chopped walnuts
• 2 1/2 cups confectioners' sugar
• 2 tablespoons butter, softened
• 1/4 cup evaporated milk
• 1/4 teaspoon vanilla extract