whipped topping mix
Dissolve gelatin in 3/4 cup boiling water; add 1/2 cup cold water and set aside at room temperature.
Mix and bake cake as directed in 9x13 pan; cool 20-25 minutes.
Poke holes in cake with end of wooden spoon, about 1 1/2 inches apart; with cup, slowly pour gelatin mixture into holes.
Refrigerate cake and prepare topping.
In chilled bowl, blend whipped topping mix, pudding, cold milk and vanilla until stiff, 3-8 minutes.
Store in refrigerator and serve chilled.