Preheat oven to 350 degrees.

In a bowl, combine cake mix, water, eggs and vegetable oil and mix until fully combined.

Spray a 9X13 pan with cooking spray and pour the cake batter in the pan.

Bake for about 25-28 minutes or until toothpick comes out clean when inserted in the middle.

Allow cake to cool completely usually about an hour.

Using the handle of a wooden spoon or something similar and poke holes in the cake making rows.

In a bowl, combine milk and pudding mix and whisk until smooth.

Pour over top of cake and spread evenly with a spatula.

Cover cake and place in fridge for about 1-2 hours or until set.

Spread Cool Whip over top and garnish with the zest of a lemon and lemon slices.

Slice and enjoy!