Hi Chris, have you already tried using a slot for drinks, and specifically a slot of type categorized? Slots and slot types are declared in the domain.yml like
slots: drink: type: categorical values: - fanta - rivella
See here in the docs: https://rasa.com/docs/core/slots/ https://rasa.com/docs/core/api/slots_api/
If you give it a try, please let me know what you found.