In a large bowl, beat vanilla pudding mix and milk. Chill in the fridge per instructions to set up.
In a separate bowl, beat heavy cream, powdered sugar, and vanilla until soft peaks form. Chill in fridge.
To assemble: In a trifle bowl or large glass bowl, layer 1/3 of the apples, pudding mix, and Snickers three times (save a few toppings for the very top). Top with whipped cream, caramel syrup if desired, and a few diced apples and Snickers.
Notes
Sometimes I fold a little of the whipped cream into the pudding mixture to incorporate the whipped cream throughout.