Answer:
Crooked as a rainbow, and slick as a plate, Ten thousand horses can't pull it straight.
It's usually found dried, but often kept slicker. Above another need, it's said to be thicker. What is it?
What is long and slim, works in light. Has but one eye, and an awful bite?
You saw me where I never was and where I could not be. And yet within that very place, my face you often see.
What can you fold but not crease?
Those with eyes bigger than their stomach will definitely leave the restaurant with one of them. It is named after a house pet as well.