1. Preheat oven to 375°F. Grease and flour 10-inch tube pan.
2. Prepare, bake and cool cake as directed on package. Meanwhile, combine pudding mix and milk in medium bowl; stir until well blended. Chill 5 minutes. Fold in whipped topping. Chill while cake cools.
3. To assemble, cut cake into 12 slices. Place 6 cake slices in 3-quart clear glass bowl. Top with half of bananas, pudding and toffee bits. Repeat layering. Chill until ready to serve.