As a disclaimer, I'm not the biggest fan of Chinese food in general. That having been said, IME/IMO CZ's food is really bad (CA and HU share a similar place in my heart, for what it's worth). Anyway, I'm standing by my "stock up at the airport" advice. On the off chance that you are so enamored with the on board food offerings that you no longer have the stomach capacity for your sandwiches, you will have no trouble at all finding a market for your sandwiches amongst your fellow passengers and the cabin crew.