I'm not exactly sure (there is little context), but "bean surprise" could be the food, a particular dish, that they are serving in the cafeteria. A lot of recipes have "surprise" in them because they are a mix of different things and a person is surprised by what is in it. I have heard of "taco surprise" and "potato surprise" as well. They make me think of recipes that use leftover foods and therefore it's a surprise because it doesn't follow a strict recipe.

'Bean-surprise' is a dish. It is a dish that is suited for a cafeteria, where you can scoop it out onto a tray easily, but many people don't like it. It's sort of like "three-bean casserole", a dish made of of three colors of string beans. In this case the beans are more like pinto or baked beans. Such a dish would have a powerful smell and not pleasant to many people.