<SNIP> With a ready to serve meal like flexible dining or the cafe car items that is all done in advance and you have a complete meal in a package.
Cryovacing, par cooking, and some other shortcuts are more prevalent in the food industry than you might think. Some of the items done properly in that fashion can be tasty. Powdered eggs, powdered milk, no. The precooked bacon must be heated properly or you get jerky. Instant grits - well, that is heresy, but they are edible. I am sure waffles, pancakes and french toast aboard AMTRAK are precooked. But they are not bad. However, comma:
Sorry ... With a "ready to serve meal" anything like "flexible dining", you have a complete mess of what MIGHT have been edible food at one time. Since my first experience with that stuff on a Chicago - Washington trip years ago, and it's current iteration, the food is either overcooked, overcooked on the outside and undercooked in the inside, stuff piled willy nilly, juices commingled, utterly inedible. The worst Swanson's TV dinners were never tihs bad.
The "salads" are a few pieces of lettuce stems, hardly any green, a couple of 1" carrot strips and two miniature tomatoes. At least there aren't cucumbers.
Frankly, I would welcome almost any of the Marie Callender's frozen meals, or even a "Hungry Man" dinner.
When we travel on the Eagle, we just bring our own in an electric cooler, and a Keurig One Cup machine.
On a positive note, the Hebrew National hot dogs are quite good.