1 pkg. yellow cake mix
3 eggs
1/3 c. butter, softened
1/2 c. water
1/4 c. lemon juice
1 (8 oz.) tub Cool Whip
zest of 1 lemon (1/2)

Filling:

1 (14 oz.) can sweetened condensed milk
1/2 c. lemon juice
2 c. whipped cream
zest of 1 lemon (1/2)

Combine cake mix, eggs, butter, water and lemon juice. Beat well. Place in 2 greased 8-inch cake pans.

Bake for 25 minutes at 375°F. Allow to cool.

Meanwhile, combine filling ingredients and mix well. When cake is cooled, slice each one in half lengthwise. Place filling in between layers of cake. Garnish with whipped cream and lemon zest. Slice and serve.