Cookie

The cookie is an edible item introduced in the Beta 1.4 update. Notch had previously mentioned it in a tweet. It requires Cocoa Beans to craft. It was later confirmed that cocoa beans would appear in dungeon chests. A full stack of eight cookies restores a total of four Hunger points (the same amount of hunger points as one Cooked Porkchop).

Advantages

 * Eating a cookie will restore half a hunger point. This is useful if you want to completely fill your hunger bar without wasting the healing potential of a more potent food.
 * The ingredients needed to make cookies can be stacked. By carrying a workbench, 64 cocoa beans, and 128 wheat, you'll be able to craft 512 cookies. This translates to 256 hunger points from four inventory spaces.

Disadvantages

 * A single cocoa produces enough cookies to restore the hunger meter as much as one cooked porkchop. However, porkchops are much easier to acquire, and a single porkchop is easier to eat than eight cookies.
 * A full stack of cookies heals a total of 32 hunger points, whereas a full stack of cooked porkchops heals 256 hunger points
 * Cocoa Beans can only be found in dungeons at the current time, making cookies highly inefficient, on par with apples.
 * Although the ingredients for cookies are a better use of stackable inventory space than the ingredients for bread, they're still not the best. 64 bowls of Mushroom Stew yield 320 hunger points. However, Mushroom Stew doesn't stack, so the ingredients (red and brown mushrooms, at least one bowl and a Crafting Table) must be carried separately. Nevertheless, at only four inventory spaces, it is a much more efficient hunger point resource than cookies, and since the bowl and workbench are both reusable, it scales up better if you want to devote more than four inventory spaces to your food supply. Also, unlike cocoa beans, mushrooms are a renewable resource.

Trivia

 * Before Beta 1.8, cookies were the only food that could be legitimately stacked (up to 8).