Cut the bottom of the strawberry just enough so it can stand up straight. Make sure you don't cut too far up or else you will create a hole in the bottom of the strawberry, and the jello will seep out. Cut the top of the strawberry straight across, and then hull out the inside using a huller or melon baller. Try not to scoop too far down or you will hit the bottom and create a hole for the jello to seep out.
Add the boiling water to the jello packet and stir for 2 minutes to allow sugar to dissolve.
Shake the Cointreau and Tequila with ice then add the cold water. Add the cold mixture to the hot mixture and stir well. Using a funnel, slowly pour the jello into the hulled strawberries. Fill all the way to the top.
Refrigerate the strawberries overnight.
Before serving, rim the top of the strawberries with salt or sugar. You can do this by dipping your finger in water than then lining the top edge of the strawberries lighly in the salt or sugar.
Top sith a slice of lime, and enjoy!
These shots do contain alcohol so don't forget to drink responsibly. :).