Soup because I've not found a single apple in almost a year of playing.
You have to kill Notch to get a red apple, and he's extremely rare.
From the wiki: Apples remained impossible to find until Survival Multiplayer. To find one, the player must kill Notch. In addition to his inventory, Notch will drop a Red Apple. The only other way to obtain apples is to hack the player's inventory.
Also, I like cake because after you have a wheat farm and have picked up some eggs, it's pretty easy to make. It can also be placed in advance for battles, and usually heals more than a golden apple because there's less wasted.