1. In a large bowl, beat the first six ingredients until well blended. In another bowl, combine the flour, sugar, salt, baking soda and cinnamon; gradually beat into banana mixture until blended. Stir in walnuts.
2. Pour into a 15-in. x 10-in. x 1-in. baking pan coated with cooking spray. Bake at 350° for 25-30 minutes or until a toothpick inserted near the center comes out clean. Cool completely on a wire rack.
3. For icing, in a large bowl, beat cream cheese and butter until fluffy. Add confectioners’ sugar and vanilla; beat until smooth. Spread over cake. Sprinkle with walnuts.