Step 1

Heat oven to 350°F (325°F for dark or nonstick pan). Grease bottom only of 13x9-inch pan. In large bowl, beat cake mix, water, oil, whole eggs and mashed bananas with electric mixer on low speed 30 seconds, then on medium speed 2 minutes, scraping bowl occasionally. Stir in chocolate chips. Pour into pan.

Step 2

Bake 38 to 42 minutes or until toothpick inserted in center comes out clean. Cool 15 minutes.

Step 3

In small microwavable bowl, microwave frosting uncovered on High 20 seconds; stir. Microwave 5 to 10 seconds longer or until very soft and smooth; spread evenly over cake. Garnish as desired. Store loosely covered.