KFC ripped off a woman who ordered the bountiful bucket of chicken she saw on TV, but got a measly 8-piece instead ... according to her new lawsuit.
The New York woman told us her story ... she went into a KFC and paid 20 bucks for the "Family Fill Up" deal -- expecting an overflowing feast -- but got cheated. She contacted KFC about the false advertising and a rep offered her a coupon for her troubles ... but she told them to eat it.
Instead, she wants the restaurant chain to pay her $20 MILLION ... though she admits that number might be a tad high -- for a good reason.
A KFC spokesperson tells us ... they've got this one in the bucket.