1 can (13.4 oz.) dulce de leche (sweetened milk caramel), divided
2 tsp. water
1 can (12 oz.) evaporated milk
1/2 cup sour cream
1-1/2 cups thawed COOL WHIP Whipped Topping
Directions
Heat oven to 350ºF.
Prepare cake batter and bake as directed on package for 13x9-inch pan. Cool cake in pan 10 min. Pierce cake with large fork at 1/2-inch intervals.
Mix 2 Tbsp. dulce de leche and water until blended; reserve for later use. Blend remaining dulce de leche with evaporated milk and sour cream in blender until smooth. Pour over cake, re-piercing cake if necessary until all milk mixture is absorbed. Refrigerate 1 hour.
Microwave reserved dulce de leche mixture on HIGH 10 sec.; stir. Cool. Frost cake with COOL WHIP; drizzle with reserved dulce de leche mixture.