HEAT oven to 350°F. Coat 13 x 9-inch baking pan with no-stick cooking spray.
COMBINE cake mix, water, oil and eggs in large bowl with electric mixer on low speed until moistened. Beat 2 minutes on medium speed. Pour into prepared pan.
BAKE 25 to 30 minutes or until toothpick inserted in center comes out clean. Cool 10 minutes. Poke holes in cake almost to bottom with handle of round wooden spoon about 1-inch apart. Wipe off handle as needed.
STIR sweetened condensed milk, 1/3 cup cream and lemon juice in medium bowl. Pour slowly into holes, spreading remaining over top of cake. Chill 1 hour.
BEAT remaining 2/3 cup heavy cream in medium bowl with electric mixer until stiff peaks form. Remove 2/3 cup. Stir in powdered sugar. Place into corner of resealable plastic bag. Reserve for garnish.
BEAT frosting into remaining whipped cream in medium bowl. Spread over top of cake. Cut small corner off bag with whipped cream. Place dollops of whipped cream (6 dollops lengthwise by 3 dollops across width for a total of 18) on top of cake. Garnish with lemon curls.