Pretend Chairman Kaga has asked you to pick the ingredient for his next Iron Chef battle. (Also pretend that Kaga is still hosting Iron Chef battles.)
He doesn’t want to duplicate anything that’s been done before.
Which ingredient do you pick?
My choice: Battle Popcorn. Bushels of pre-popped and unpopped kernels. I’d love to see what the chefs could do with that.
Have they done 'gator before? Or rattlesnake? How about jerky?
Fugu. Definitely fugu.
Porcupine will do in a pinch. 
Play-Doh.
What? It’s non-toxic, and I ate a ton of it as a kid…
Circus peanuts.
Battle Vegemite!
Soylent GREEEENNU!
Pan-fried semen
Lobster Tomalley (lobster liver, sickly green, salty, and revolting)
Spam (surprised no one suggested this yet)
Soylent Green (actually, Futurama’s parody “Iron Cook” tackled this one)
Human 
Iceberg lettuce.
That’d stop them dead in their tracks.
Possum!!
Ketchup!
Water
Corn chips
Actually, just corn (not the popping variety).
Beer
Vodka or any other hard liquor.
An choice I’ve always wanted to see, especially timely right now:
Today’s secret ingredient is…
MATZAH!!!
Spam
Lime Jello
Velveeta
Various pieces of “fortune teller” Kazuko Hosoki. Coin flip determines who gets the head.
Either haggis, or maple syrup.
“Fukui-san!”
“Go, Ota?”
“The challenger is mixing the haggis with heavy cream, and putting it into the ice-cream maker! Looks like we have a dessert!”
“Heart, lung, liver and lights! Sonsie, is it not?”
Rocky Mountain Oysters.