Preheat oven to 350.
In large bowl mix together your cake mix and ingredients required.
Pour into a prepared 9"x13" pan.
Bake for about 30 minutes or until center is set and toothpick comes out clean.
Once cake is done, poke holes all over the top and set aside.
In another bowl, mix together your jello, water and sweetened condensed milk.
Pour jello mix over the top of cake and spread into holes, chill for about 1 hour.
Meanwhile to make frosting, in bowl whisk together your pudding and milk until it just starts to get thick, fold in your cool whip and orange zest.
Spread over chilled cake.
Top with more whipped cream and quartered orange slices if desired.