Add the water, Apple cider vinegar, kosher salt, and sugar to a medium saucepan and bring to a boil, stirring to completly dissolve the sugar and salt. Remove the brine from heat and set aside.

Pour the hot brine over

Pour the hot brine in the jar, filing it and covering the carrots. Use a pickle weight if necessary. Allow to cool and then store in the fridge. The Firecrackers are ready to eat in 3 days.