Which, I learned from our boulangère and her freezing glance, is not how you ask about a piece of viennoiserie.
I’d like a wooden tray, about 50cm by 50cm, 35cm tall, on wheels, to keep stuff in, at the bottom of a cupboard. The wheels are so I can wheel it out.
I’ve no idea what I’d call it in English, let alone French.
Any ideas?
Chariot de service would be my guess. Maybe add à roulettes.
Tiroir à roulettes maybe? Or cagette?
C’est quoi ce truc là might be appropriate for eg a weird insect on a rose, a newly noticed wart, a Heath-Robinson device…
Used in a similar manner to “What the **** is that?” by the French in my part of the world.
Often followed by “C’est pas normal.” in the tone one would use having just found a human finger inside of a packet of Merguez sausages.
@Porridge - how about getting a wooden box and putting roulettes on the bottom? You can get packsof those from any bricolage place…
I’m thinking perhaps this sort of thing?
I love you, @AngelaR , because you think I am capable of the most basic of bricolage
when in fact I am banned from doing anything like that
even the hooks I stuck to the wall, to hang slotted spoons etc., have all fallen to the floor
during the night
with a clatter
We are talking incredibly basic bricolage - I’m sure you can use a screwdriver if the screws are already provided?
(And I’ve given up ever buying the hooks with sticky backs as, in my experience, they NEVER work. Likewise those things with suction cups on.They work for a maximum of a week before sliding off the wall 
)
How’s your other half with basic DIY?
You see, you’re already miles ahead of me!
Worse.
It’s hereditary.
One of my USPs with her dad was that I could change a light bulb: before me, they had to get the handyman to do it.
(A lot of the time I joke, but that is the literal truth.)
Presumably she thought you were criticizing her pastries. 
A ‘Low Tea’ trolley perhaps.
I would like to help but yoir initial statement/question doesn’t make sense to me. Did you want to buy a viennoiserie OR the hostess trolley you’re talking a out? If you clarify, I’ll try and help as it’s mainly a language issue but perhaps cultural difference.
Thanks, @frenchy. My hostess is off her trolley! I think my question was resolved.