Preheat oven to 350 degrees F. Prepare the box mix according to package directions for a 9-inch x 13-inch pan. Bake and cool cake completely, about 1 hour.
Cut cake into cubes and loosen from pan. Prepare vanilla pudding according to package directions using the milk.
In the bottom of a large glass serving bowl or a trifle bowl add half of the cake cubes. Top the cake with half of the pudding, and half of the sliced bananas.
Add the sliced strawberries around the edge of the bowl pressing them to the sides. (This makes the layer look pretty on the outside of the bowl.) Sprinkle the rest of the strawberries over the bananas.
Add half of the crushed pineapple over the strawberries. Top the fruit with half of the Cool Whip, half of the chocolate syrup, half of the walnuts, and then all of the chopped cherries.
Repeat the layers - cake, pudding, bananas, pineapple, Cool Whip, chocolate syrup, walnuts, and top it all off with the whole cherries.
Cover with plastic wrap and refrigerator for 1 hour. Keep chilled until ready to serve.