Heat oven to 350°F Lightly grease or spray 13 x 9-inch metal baking pan with cooking spray.
In large bowl, combine cake mix, oats, water, milk, egg whites, oil, vanilla and almond extract. Beat 2 minutes with electric mixer on medium speed. Gently stir in 3/4 cup mini chocolate chips. Spread evenly into pan.
Bake 30 to 40 minutes or until top springs back when pressed in center. Cool completely in pan on wire rack.
For frosting, combine powdered sugar, butter, vanilla and marshmallow creme in medium bowl; mix until smooth. Spread frosting over top of cooled cake. Sprinkle with coconut, if desired, and remaining 1/4 cup chocolate chips.