I like to use cooked chicken as my food source. I have a completely automatic chicken farm that breeds, cooks, and collects. It is easy to set up, and provides a lot of food if you can get a lot of chickens inside the egg-laying chamber.
I use pumpkin pie and baked potato. When hungers falls below 3 joints first eat a pie and then a potato to have higher saturation. You're better off with cooked meat or salmon instead of potatoes, but I'm a minecraft vegetarian.
For the most hunger points, eat Rabbit Stew, it gives the most for 10 hunger points.
For saturation, eat golden carrots, as they give 14.4 saturation points, the most in the game.
But, my preference is either golden carrots or pumpkin pie. They are both relatively easy to make, once I have a pigman farm going in the nether, I can easily stock up on gold and carrots, and pumpkin pie only requires some sugar, pumpkins, and eggs, for 8 hunger points.
I think bread is the most practical. Easy to find seeds, fairly easy to grow and harvest, and easy to replant. Sure it can take a while for enough wheat to grow, but once you get a farm going it's mostly self sustaining (provided you replant the seeds each time you harvest the wheat), and allows you to continually expand your garden as well. Also you aren't as susceptible to wasting hunger points with bread as you are with meat and other items that restore four hunger points.
The Meaning of Life, the Universe, and Everything.
Let me take a slightly different look at this. The OP said the reason was for long journeys. Depending on the definition of long journey, the answer may be, don't worry about it. I take a stack of what ever is available with me when I go on a walk about. But I also have a bunch of coal in the inventory. If I start to get low on food, I just start wacking cows (or pigs or chickens or sheep, what ever is plentiful) until i have enough raw meat. Then craft a bench and a furnace, then cook the meat up. Simpler as I'm not taking up storage space on stacks of food.
Carrots. It does not need to be cooked, or crafted, or anything. Carrots are literally Minecraft's version of fast foods: fast, does not require additional effort on the player's part, and is very good for those who just want to eat without having to do stuff.
I used to just farm bread and eat bread(and Rotten Flesh) exclusively, then carrots became a thing.
I would have to say a Mooshroom farm is the best food source. All you need is a wooden bowl and a Mooshroom and you have infinite mushroom stew which restores 3 hearts, you don't even need to cook it. Of course finding and getting the Mooshrooms back to your base may prove difficult... But once you have your Mooshrooms mushroom stew is definitely the laziest and cheapest source of food, and of course they drop steak too which has the highest saturation in the game. After that I'd say baked potatoes.
I would have to go with cooked Porkchops/Steak. Though you can get many melons from one farm, melons are very difficult to find. You can find pigs and cows anywhere, and it doesn't take much to cook them.
I just read at least 100 replies here and I am surprised there is not a SINGLE comment about my favorite Minecraft food?
BAKED POTATOS, it seems so many people don't understand what saturation is. Baked Potato's restore 5 hunger points and have a saturation of 1.2 which is very close to cooked meat! (steak and pork chops give 8 hunger and 1.6 saturation) they also stack to 64 and harvesting a small grid of potato's can yield massive amounts of food as you almost always get 2-4 per crop. no breeding, no killing, no animal pens, no bowels no intensive eating ritual, and potato's can be hurried with bone meal! I grow them inside buildings and caves with torches for light so no mobs can harm me while I collect my food. Potatoes are difficult to find if you have no villages however if you stay up a few nights and keep killing zombies they will eventually drop a potato and you can mass produce from the one you get as loot. Why has there been no mention of this minecraft superfood??? personally, once I get a potato in my game I immediately discontinue all other food production. I hope some of you give baked potatoes a try I am way to active in game to eat melon slices and cookies I would have to eat constantly if I eat those foods they have so little saturation! I mean come one how are so many of you suggesting cookies? with a saturation of .2! and melon .6! I guess if you don't explore or mine but even then im baffled.
Please take a look at the official minecraft wiki and look up HUNGER there is some great info on that page!
Landon1976 - I completely agree. once you find a potato they are very easy to get a large farm going. You knock all the potatoes out, replant, go to a furnace and throw the stack in and walk away. Once you do this a couple times you should have furnaces packed full of potatoes - It's very easy to get a chest full of baked potatoes - and if you want to make things easier just set up an automatic furnace