Some of the food needs to be eaten, not all, which can work in your favor. Actors could eat eggs and biscuits, but not get around to eating the sausages and fruit which could be fake and thus be cleaned and reused.  So a plate of sausages and a plate of fruit could be passed around the table, but never actually eaten.  When Helen throws them they make a mess, but not hellacious and sticky mess.

Remember that this is one of two of the most famous scenes, and incredibly moving. ... be careful of making it too 'clean' - it will really alter the reaction to the scene. And it needs to be pretty miserable to provide the contrast to the wah-wah scene later.

It would be more effective to figure out how to clean up the mess, and for the director to have specific areas (perhaps on a carpet that can be removed from the set?) to stage the worst of the fight.

The production I'm in will be using torn up bread for the eggs, and rye bread cut in strips for bacon.

We used cold polenta which looks a lot like scrambled eggs when it's broken up into chunks.  Plus it keeps well for a few days.  Also used bisquits and ham along with it for "realism."  But the polenta is what Helen threw.  It was relatively easy to clean up.

Fondant is a brilliant idea...for just about any food, in any play.  I'll have to remember that.