In a saucepan, combine the sugar, cornstarch and gelatin; stir in water until smooth. Bring to a boil; cook and stir for 2 minutes or until thickened. Remove from the heat. Stir in strawberries; set side.
In a large bowl, combine milk and pudding mix. Beat on low speed for 2 minutes set aside. Toss bananas with lemon juice; drain and set aside.
Place half of the cake cubes in a trifle bowl or 3-qt. serving bowl. Layer with half of the pudding, bananas, strawberry sauce and whipped cream. Repeat layers. Cover and refrigerate for at least 2 hours. Garnish with additional fruit if desired. Yield: 14 servings.