I’ll often choose an after-dinner drink, because I usually stuff myself during the main course. Maybe I’ll order an Espresso Martini. Or I’ll go full Dude and order a White Russian. Or whatever else looks good.
When stumped, I’ll ask the server for a suggestion. I try to give them something to work with, like “sweet”, “creamy” or “citrusy”.
As long as they’re not an intolerant dick about believing or not believing, whatever they go with is fine. It’s none of my business.