Allspice is the dried, unripened berry of the myrtle pepper tree, or pimento, which is native to Jamaica and much of Central America. The berries are briefly fermented, then sun-dried until brown.
 
Often mistaken for a blend of spices, allspice is a single-ingredient seasoning with loads of unique flavor. Allspice's flavor evokes a blend of nutmeg, cloves and cinnamon. You can use it in place of any of those spices, and then some.