Heat oven to 350*F. Spray 9-inch square pan with nonstick cooking spray. In large bowl. beat sugar and margarine until well blended. Add bananas vanilla and egg; mix well. Lightly spoon flour into measuring cup;level off. Add flour, baking powder, baking soda and 2 teaspoons ginger to margarine mixture; mix until moistened. Add milk; mix well. Pour into sprayed pan. Bake at 350*F. for 25 to 35 minutes or until toothpick inserted in center com es out clean. Cool slightly. In small bowl, combine all topping ingredients; mix gently. Cut cake into squ ares serve warm or cool topped with whipped topping mixture. Makes 9 servings.