Persistent Distraction

The monkey comes out of the sleeve

Auntie Shell loves expressions that feature monkeys. "De aap komt uit de mouw!" is used to remark upon the revelation of crucial detail that was previously withheld, or a hidden agenda finally made clear.  It literally means, "The monkey comes out of the sleeve."

Colleague #1:  "I just failed my certification exam."
Colleague#2:    "Oh, drag.   But I'm surprised...
Colleague #1:  "Yeah, well, I thought it was scheduled for next week."
Colleague #2:  "Ahh...there comes the monkey out of the sleeve!"

Tell it to the cat

Another expression of skepticism.  If a Dutch person doesn't buy what you're selling, he'll say, "Jaja, maak dat de kat wijs."  He figures you'd be better served to tell the cat your story, if you want someone to believe it.

Colleague #1:  "Where have you been all morning?  I've left you two voicemails."
Colleague #2:  "I've been super busy."
Colleague #1:  "Yeah yeah, tell it to the cat."

With your mouth full of teeth

If a Dutchie is speechless, he just stands there "met de mond vol tanden."   

What could express the inability to speak better than this?  The brain desperately searches its database for words, but nothing makes it as far as the mouth, which simply continues its teeth-storage duties.

Proposed usage:

"Two days after I threw out everything in the ancient hardware storage room, somebody asked me for 25 power cords and a Spanish keyboard.  I just stood there with my mouth full of teeth."

Monkey-sandwich story

Usually applied to grisly, ironic, or otherwise unusual stories of kittens in jars, criminal plots gone wrong, super-expensive cookie recipes, outrageous acts of revenge committed by spurned lovers, and, presumably, unsavory dishes unwittingly eaten, the Dutch equivalent of "urban legend" is "broodje aap verhaal."   

Because such stories are presented as true but are almost always fictional, I'd like to see the literal translation of "broodje aap" used, as I have heard at our international office, to express skepticism:

Colleague #1:  "When I was a child I once defrosted the windscreen of my mother's car with an electric sander."

Colleague #2:  "Monkey sandwich, mate.  Monkey sandwich."