Peanut

From SmashWiki, the Super Smash Bros. wiki

The Peanut is an item which is sometimes left over when a shell of one of Diddy Kong's Peanut Pop Gun projectiles shatters. They also can come from the shots fired during Rocketbarrel Barrage. It can be eaten to recover a small amount of damage (2% actually).

[edit] Trivia

• For some reason, there can be only 4 peanuts at the same time on a stage.