There are a number of YouTube videos on duplicating or improving the MRE.
I used to keep some around but gave up as the Mountain House stuff was better tasting and longer lived.
Way back when, we kept two “issue” MRE’s in our ‘situation’ bags in the patrol cars, in case something happened and we were stuck for a long period of time.
I don’t keep any around any longer, my money is better spent on better food. And you can slurp a can of spaghettio’s cold right out of the can. Personally I find it more appetizing than the MRE spaghetti.
I have friends who existed on MRE’s for long periods of time, one commented that the only hot meals he got were when he was out with the natives, and then you just didn’t ask what was for dinner.
I am reminded of the POW’s in the concentration camps and military camps. When liberated, a number of people died from the richness of the food they were given. Their systems couldn’t handle it yet. 3000 calories is quite a bit more than some can handle now.