Da-daup

equivalent to "I'm kidding", ESPECIALLY: used after stating a reasonable hyperbole to clear up misunderstanding

Voice 1: "My boss is a real prick."
Voice 2: "Oh?"
Voice 1: "Yes, if you use LibreOffice instead of Microsoft Word to turn in your reports, he'll fire you."
Voice 2: "Wait, what?"
Voice 1: "Da-daup."