Add the jello mix and boiling water to a medium mixing bowl; stir until dissolved.
Add lemon lime soda and vodka and stir again.
Line 15 shot cups on a rimmed baking sheet or flat surface that you can easily move.
Using an injector or pourable measuring cup, fill each shot cup about ¾ of the way full. Do not fill to the top.
Place in the fridge to chill for 2 hours, or until set.
Just before serving, top with a dollop of whipped cream and a lime slice, if desired. Enjoy!
Notes
I used strawberry gelatin for this recipe, but you can use any other red flavor that you like.For the best flavor, use a name brand lemon lime soda. However, any lemon lime soda will do the trick. I definitely suggest using a higher quality vodka. Cheaper vodkas give the Jello an unappealing, chemical flavor. If you don’t plan on serving these as soon as they set up, don’t add any garnishes. Just put the lids on them and leave as-is. Add the garnishes right before serving. Ungarnished shots can last up to 2 weeks in the fridge if stored with lids on. Don’t store them without lids or they will dry up and get leathery. Don’t freeze.I use an injector, because it guarantees less mess and makes the process quicker. A pourable measuring cup also works pretty well. To make these virgin, replace the vodka with more lemon lime soda or cold water. Both will work well.