Step 1

Heat oven to 350°F. Spray bottom of 13x9-inch pan with cooking spray.

Step 2

In large bowl, beat Cake ingredients with electric mixer on medium speed 2 minutes, scraping bowl occasionally. Pour into pan.

Step 3

Bake 28 to 33 minutes or until toothpick inserted in center comes out clean. Cool in pan on cooling rack 5 minutes. With handle of wooden spoon (1/2 inch in diameter), poke holes almost to bottom every 1/2 inch, wiping spoon handle occasionally with paper towel to reduce sticking.

Step 4

In medium bowl, beat Filling ingredients with whisk about 2 minutes or until starting to thicken. Pour over cake; spread evenly over surface, working back and forth to fill holes. (Some filling will remain on top of cake.) Refrigerate about 2 hours or until chilled.

Step 5

When ready to serve, drop whipped topping by spoonfuls over cake; spread evenly. Sprinkle with chocolate shavings. Cut into 5 rows by 3 rows. Store loosely covered in refrigerator.