1Beat the first five ingredients with mixer until well blended.
2Cut each cake horizontally into 2 layers. Stack on plate, spreading 3/4 cup frosting between each layer. Frost top and side with remaining frosting.
3Microwave chocolate and cool whip in microwaveable bowl on High 2min or until chocolate is melted and mixture is well blended, stirring after each minute. Cool 15min; spread over top of cake allowing
excess to drizzle down side. Keep refrigerated.