Question: What can you do if you are baking cookies and don't have an egg?
Options:
Mash up 1/2 a banana leaf for every egg you need.  It will substitute for it.
Mash up 1/2 a banana for every egg you need.  It will substitute for it.
Answer: Mash up 1/2 a banana for every egg you need.  It will substitute for it.