The Overlord wrote:
I think it happened in "The Last Outpost".
Yeah, but that wasn't intentional, the Ferengi were supposed to legitimate villains in that episode, its just the execution that failed.
They were still presented as legitimate threats in "The Battle" "Peak Performance" and "The Price". It wasn't till "Ménage à Troi" that the writers presented them in an intentionally goofy way.
They were never very threatening.