Prepare and bake the cake ina 13x9 pain according to package instructions.
Let cool completely. Then Poke holes across the cake with the bottom of a wooden spoon.
Be sure to poke all the way to bottom of the pan.
In large bowl, whisk together pudding, milk, and vanilla, but don't let it thicken.
Pour the thin pudding over cake in an even layer, poking down into holes if necessary.
Refrigerate the cake for one hour.
Place the chocolate chips and corn syrup in a heat-proof bowl.
In small saucepan over low heat, warm the cream until it simmers, stirring occasionally.(you could also put cream in microwave unti hot)
Pour hot cream over chocolate chips and let sit for 2 minutes to melt.
Stir until smmoth. Let the glaze cool for 10 minutes
Pour glaze over cake and smooth with a spatula.
Chill cake for 4 hours or overnight before serving