Sift the cake flour, baking powder, baking soda, and salt, blending welland set aside.

Place the vinegar in a measuring cup. Add enough milk tomake two third cup and set aside. Cream the shortening and sugar together, in alarge mixing bowl, until light and fluffy, using an electric mixer set onmedium speed. Add the eggs, one at a time, beating well after eachaddition. Add the dry ingredients alternately with the milk mixture andbananas to the cream mixture, blending well after each addition, using lowspeed on the mixer.

Stir in the walnuts and pour the batter into a greased13 X 9 X 5 cm baking pan. Bake in a preheated 180ºC . oven forabout 45 minutes or until a cake tester or wooden pick inserted in thecenter comes out clean. Cool, in the pan, on a wire rack until cold to thetouch, then frost.

PENUCHE FROSTING:

Heat the butter in a 2 litre saucepan, over medium heat, until bubbling butnot browned. Stir in the brown sugar. Cook, stirring constantly, untilthe mixture comes to a boil. Reduce the heat to low and cook, stirringconstantly, another 2 minutes. Stir in the milk. Increase the heat tomedium and cook until the mixture returns to a boil. Remove from the heatand cool to lukewarm. When the mixture is luke warm, stir in theConfectioners' sugar and beat with a wooden spoon until well blended andthick enough to spread. If necessary, place the pan in a bowl of ice waterand beat with a wooden spoon until the frosting reaches a spreadingconsistency. If the frosting becomes too stiff, warm over low heat.