Most recipes are "more like guidelines, anyway" when it comes to their ingredients and procedure. But when it's a healing potion you're dealing with, best to be as precise as possible. That's what you'll be trying to do in the new scenario for Zombicide: Black Plague and No Rest for the Wicked, available to download for free now.
From the post:
Here’s the thing about healing potions and spells… If you mess them up, you raise the undead instead of healing the wounded. Now, Baldric needs to find Nelly and escape with the ingredients before it’s too late.
This is a solo mission for Zombicide: Black Plague and No Rest for the Wicked.