make the bread: Preheat the oven to 350 degrees. In a small bowl combine the milk and the vinegar and let the mixture stand for 15 mins. In the bowl of an electric mixer cream together the sugar and the butter until the mixture is light and fluffy and beat in the eggs and the vanilla, beating until the mixture is smooth. Stir together the milk mixture, baking soda, salt and baking powder, beat the mixture into the butter mixture in batches, alternately with the flour, beginning and ending with the flour, and beat the batter until it is smooth. Fold in the walnuts and the bananas, pour the batter into a greased loaf pan, 9x5x3", and bake the bread in the middle of the oven for 1 hour, or until a tester comes out clean. Let the bread cool in the pan on a rack for 15 mins. And turn it out onto a plate.

make the glaze: In a food processor blend the confectioners' sugar, butter, vanilla, milk and salt until the glaze is smooth and creamy. Drizzle the bread with the glaze and let it stand for 10 mins. Before serving.