The Apple is an item that would make several appearances throughout the Mario series.
 Game History
 Paper Mario Series
 Paper Mario
In Paper Mario, the Apple can be found in Boo's Mansion and can be found in the crates of the mansion after Spin Jumping on the crates. When they are used, it can heal five HP though it can be used for cooking.
 Super Paper Mario
In Super Paper Mario, it would be called Red Apple. It would also introduce other apple items like the Black Apple and the cursed Golden Apple, the mustache-inducing Yellow Apple, the fruit-transforming Pink Apple, and the shrinking Blue Apple.
Related Threadschapter 7-3: no more red apples - last post @ Jul 25, 2012
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where is the apple and whats the recipe for apple pie? - last post by @ Sep 13, 2003