Replacing the opponent's argument with a made-up version that's more easy to disprove, and addressing the latter as if it was equivalent to the former.

General form:
"Not B" (where the opponent stated A)

Typical example:
"I'm fed up with bread; we ate nothing but it for a week."
"We'll starve if we don't eat anything!"

An argument can only be refuted by addressing the argument itself. Refuting an argument the opponent never made (even if the refutation is flawless) does not prove the opponent wrong.