Along with the better known Decanters of Endless Water & Daily Bread Pouches (which produce enough fruit bread to keep four people fed for a day), you’ll occasionally find larger serving boards that can conjure a whole feast.
Unfortunately what you’ve stumbled across may also turn out to be a Groaning Board. It isn’t the board that’ll be doing the groaning, though – it’ll be the diners. Anyone seated at the board when it’s activated will be assailed by a low-level demon that proceeds to strip them of their gear & then force feed them toads & jagged rocks, chased with ladles of boiling vinegar.
You can fight off your Abyssal server with moderate effort, but they just keep on coming unless you & your wannabe dining companions manage to smash the board.