Here's some recent experiences:
CVG-SEA on A320 at breakfast time -- Pretty good hot omlette
SLC-STL on A320 at dinner time -- Soup & sandwich or Soup & Salad -- I think the soup was brought in a thermos though...
STL-SLC on A320 at breakfast time -- Cold breakfast (cereal, yogurt, etc)
I guess the CVG-SEA was hot because it was over 1500 miles.