Viet-Cajun crawfish recipe? (I did search…)

The few links in the old sticky and the threads I could find in search are years old and not very specific recipes – they say things like "add your favorite boil mix, some butter, boil it for a while"… And that might be enough for experienced folks doing a boil, but this'll be my first.

And I moved to Ireland, so I don't have access to a lot of things you might take for granted (although the butter is definitely better here!). Can someone share a detailed recipe for Viet-Cajun crawfish? Preferably as "from scratch" as possible, since ordering stuff from the States costs me eight and a half metric feck-tons of dollars?

Slainte,

A Tex-Pat living in Ireland who misses mudbugs a LOT