Asklemmy

That's just long enough for things that aren't shelf stable to start going bad, depending on local conditions. Bread can mold in a couple days though, in warm and humid places.

So, focus in on shelf-stable or preserved things, whether made in a modern method, (sterile packaging of some sort) or an old fashioned method, (drying, curing, smoking) or just naturally able to keep (nuts, seeds, chocolate, honey).

Someone posted their granola bar recipe, that looked pretty solid. I would certainly not bring a bunch of pasties or a calzone unless I was also bringing a cooler. Then I'd be bringing ingredients and tools and making them on-site just for fun, as I assume I'm now car camping, or at least camping fairly close to my vehicle. If backpacking in, then absolutely not. Ready-to-eat, shelf-stable stuff only, to cut weight and stay efficient. And a pasty or calzone would squish in the backpack and end up gross anyway.

What I found to be quite interresting and working well are the solid fuel stoves from esbit. You should be able to bring them on a flight and one small tablet lasts long enough to boil enough water for some instant ramen, soup or a cup of instant coffee.

I highly recommend getting a gas burner, if you are comfortable with it. It’s great for cooking while camping. We’ve recently made tacos and risotto while camping. Also, depending on the brand/model, it works in most weather and you’re not reliant on gathering wood for a fire.

Get some mason jars and do oldschool canning. Food will stay preserved well as there's no bacteria at the temperature you put it in there, and no air will get in.

Toss in some macaroni and pasta sauce, goulash, tomato soup, premade cup-o-noodles with your favourite veg and protein. Your imagination is the limit.

You can get either canned or dried fruits and veggies that last longer un-refrigerated and have some nutrition to them. Obviously there's power bars as well. Dry cereal if you don't mind eating it dry, makes a decent snack too, or bring powdered milk if you do want to eat it with milk. I've heard freeze dried foods are popular with backpackers. Bananas last long enough if you get them fresh enough. I think there are other fruits and veggies that you don't need to refrigerate for them to last long enough, like tomatoes, cucumbers, oranges, pears, kiwis, apples, etc, just as long as you eat the whole thing in one go cause they don't last as long once they're cut or bit into. Oh and fruit cups are also an option. And of course there's bread, but if you want some variety there you can make/buy some banana bread to take with you as well. Popcorn also lasts quite a while if kept in a sealed bag. You can also eat ichidan or other dry packaged noodles dry, just break them up into smaller pieces in the bag, take out the flavour packet, and either pour the packet into the bag, or pour the noodles and flavouring into a bowl, and mix it up. Tastes pretty good, and makes for a good snack. Not very nutritious, but cheap and easy. There's also pop tarts, which can be eaten cold.

Those are the ones I can think of off the top of my head. You don't need to take all of them for just 4 days, but it's nice to have options.

You can dehydrate literally anything, and re-hydrate it on the trail with a little water and heat. Meats, Fruits, Vegetables, Soups, the works.

Babybel cheese

Mcdonalds cheeseburgers. I saw a video of a guy doing the pacific trail with just a bag of hamburgers and he said they lasted sell over a month. He also said its the best thing hes ever done as they gave him more strength than protein bars ever have. I couldnt find the hamburger but i found mcdouble guy

Can’t you just bring a Trangia stove? They burn for EVER on half a litre of spirit.

Fruits, rice, pasta

Edit: dont do rice, it’s a bad idea