What I'd do Mate is...
Find out what they like, don't like or any potential allergies.
Cook them something that is a local speciality, a way of cooking or a food that is mostly special to your location.
Find out how they like to eat, eg; Some prefer 'homestyle' informality, others like (and expect) a more formal setting, some are quite happy to get round early and help you prep and cook the food.
Hope that helps....and I guess, don't try and source some kangaroo or emu steaks for them!
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