1 box white cake mix
3 ounce lime Jello
8 ounce Cool whip
1 cup boiling water
1/2 cup cold water
Prepare and bake white cake as directed on package. Let cool 15 minutes.
Combine Jello and boiling water until well combined. Stir in 1/2 cup cold water.
Poke cake with fork about every 1/2 inch. Pour Jello mixture over cake.
Refrigerate for 3 to 4 hours. Frost with Cool whip.