Heat oven to 350 degree F. Line a 13 x 9 x 2-inch baking pan with nonstick foil. Set aside.

Cake: In a blender, combine 1-1/3 cups water, the bananas, egg whites and oil. Blend until smooth, about 1 minute. Place cake mix in a large bowl and add mixture from blender. With an electric mixer, beat on low speed for 30 seconds, then increase speed to high and beat 2 minutes. Pour into prepared pan and bake at 350 degree F for 33 to 35 minutes.

Cool cake in pan on a wire rack for 15 minutes, then, using foil, lift cake from pan and cool completely.

Filling and Fruit: Meanwhile, cook pudding mix with milk for 15 to 20 minutes over medium heat, until thickened and bubbly. Transfer to a bowl and refrigerate 30 minutes.

Trim edges from cooled cake. Cut in half, then cut one half into cubes (about 20). Place in a trifle dish or bowl and press slightly to compress. Spoon 2 cups pudding over cake. Top with 1 sliced banana and 1 cup of the sliced strawberries. Cut second cake half into cubes and continue layering cake, pudding, bananas and strawberries. Top with heavy cream. Refrigerate at least 3 hours or overnight.