Storage and monkey sacrifice zone
Next to the Kitchen and the Bar is the Catering Storage, jam-packed not with actual jam, but with all of the tools a Chef might need not found directly in their Kitchen. There's also some extra glassware and a still for the bartender!
Among the stuff for the chef in particular - there's an ingredient processor, a reagent extractor, and a monkey dispenser. The dispenser is useful since the Freezer room in the top area has meatspikes you can use to instant kill a monkey and harvest their meat... as well as a gibber, to do the same with humans. Oh, and there's a pizza vending machine, in case your own food is ruined and you need some fast food to disguise as your own.
Finally, the Catering Router in the bottom-left is handy to ship out and receive food-related goods from Cargo, and any other department with a router.
There is no vent. No need to worry about monkeys escaping.
The APC for all four rooms is on the main area's top wall.