Any particular part of Europe? It's a pretty big place LOL.

What is the food for - do you want savoury (main meal) type food, savoury snack, or dessert / morning tea type stuff? Do you have facilities for reheating or does it have to be served cold?

If you really want to do quick and easy, you can always buy a pannetone (Italian celebration cake) from a good European grocer or deli. Or some good croissants, or an antipasto platter with some Italian bread.