Adding bonus Cantrips

[Vex]

I am trying to find a way to add a bonus cantrip to a spellcasting class. The cantrip gained will be dependent upon the caster class (e.g. Druid = Druidcraft, etc.) , but I am fine with it being a selector if that is easier.

I have tried to copy and replicate function from Magic Initiate as was mentioned in another thread here, but wasn't able to get it work. I tried to model it as an adjustment based on the existing Adjust Spell Slots, but was unable to get it to work for Cantrips. I can't seem to find the cantrip equivalent for SlotHold0 like there is for every other spell casting level.

I'm fairly inexperienced with the editor and have been searching and banging my head on how to do this. Any direction is greatly appreciated.