To rim the shot glasses: Place a small layer of caramel sauce on a shallow plate or saucer. Dip each shot glass into the caramel sauce.
Add jello mix to a medium-sized bowl. Pour boiling water in and whisk until the Jello is fully dissolved--about 2 minutes.
Stir in caramel vodka and sour mix. Allow the mixture to cool for about 20 minutes at room temperature. Pour evenly into shot glasses and refrigerate until set, about 2 hours (or overnight).
Top with a thin layer of caramel and apple wedge before serving.
Notes
Place your jello shot cups in a baking pan or muffin tin for easy transport to and from the fridge for chilling.Make your jello shots the night before your party if possible, so that they will have plenty of time to set and you won't have to worry about making them the day of your event.