Pour the gelatin powder into a medium mixing bowl. Add the boiling water and whisk until the gelatin is dissolved.
Add the ice cubes, Sour Apple Pucker and both vodkas. Stir well until the ice cubes are melted.
Pour the gelatin into each shot glass but not all the way up to the top of each glass - you will want to leave room for the caramel sauce.
Chill for at least 2 hours.
Remove the shot glasses from the refrigerator and add the caramel sauce, filling up to the top of each glass.
Keep chilled until ready to serve.