Pour into 2 greased and floured 9-inch round pans.
Bake 28 to 30 min. or until toothpick inserted in centers comes out clean. Cool cakes in pans 10 min.; invert onto wire racks. Gently remove pans; cool cakes completely.
Spoon frosting into medium bowl.
Add COOL WHIP; whisk until blended. Stack cake layers on plate, filling and frosting with COOL WHIP mixture.