Preheat oven to 350 degrees F. Grease a 9×5 inch loaf pan.
In a bowl, whisk together the flour, baking powder, and salt; set aside.
In the bowl of your electric mixer, beat together the banana, sugar and eggs until smooth. Add the vegetable oil, milk, and lemon juice and beat until smooth.
Pour batter into prepared loaf pan & bake 55 – 60 minutes or until a toothpick inserted in the center comes out clean.
Cool 5 minutes then remove to a wire rack to cool completely.
To make the glaze, Whisk powdered sugar, lemon juice and butter until very thick and white. Spread this lemon juice frosting over the top of the cooled loaf.