Mix in 1/4 cup of apple juice and 3/4 cup of fireball whiskey
Pour the gelatin mixture into the shot cups and cover.
Refrigerate until they have gelled, 2 to 4 hours
Video
Notes
Putting the shot cups on a cookie sheet catches any spills and makes them easier to move into the refrigerator.
For a stronger or weaker jelly shot, adjust the amount of apple juice and Fireball whiskey. Just make sure that the total amount of cold liquid added is 1 cup.
You can also replace the apple juice with Apple Pucker (or Schnapps) if you want it stronger.
Substitute cold water for the apple juice for slightly less apple flavor.
To prevent water from condensing on the shot cup lids, wait until the gelatin liquid has cooled completely before covering it.