The Glee star was speaking about her love of food during an appearance on The Tonight Show, when she told the host the only thing she refused to eat was sushi.
She said, "I hate sushi... It looks like it's wrapped in plastic... I won't ever eat fish. I hate the smell, taste, texture, all of it and I told you I would only eat sushi if you made a donation to my charity Maddie's Corner... But you have not done that."
Leno then presented the pint-sized beauty with a plate of the spiny creatures and a $500 (£312.50) cheque to her organisation, which rescues stray cats and dogs, prompting Chenoweth to scream in horror.
She squealed, "It looks prickly. It looks like a porcupine! Oh my God you guys, there's a worm in there!"
The 44 year old then swallowed a large bite, gagging along the way, before adding, "That tastes like c**p... Why would anyone pay for that? That's offensive. Thank you... and I appreciate it, but I will never make that bet with you again."
Leno was so impressed by Chenoweth's bravery, he doubled his donation, stating, "I'll tell you what, you were such a good sport, we'll make it a thousand."