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Don't pack anything that needs to be cooked or rehydrated. Preferably, no canned foods either, although the cheapest sources of shelf-stable protein are always the canned stuff so I do see the attraction. I guess you could pack some canned protein (chicken, SPAM, tuna, etc.) and jettison it if you needed the space or the reduction in weight. Some of the weight in those foods is water weight so you should keep in mind that you're also going to be able to hydrate with the contents of those cans (assuming you aren't an utter idiot and that you don't drain the tin before you consume the contents).
Myself, I have my bag packed a little heavy and a LOT full, but the intention is that I will jettison or stash anything that isn't relevant to the immediate situation/season ASAP. I also have, folded flat and stuffed into an exterior pocket, a lightweight drawstring "packpack" that I can use to divide my load if I join forces with someone who is less burdened.
Pic related.