"Il cuoco ha un arrosto nel piatto."

Translation: The cook has a roast on the plate.

[concifuriram]

This doesn't make sense in either language...

[lightgreen]

"Can I use that plate yet?" "Sorry, no. The cook has a roast on the plate."

[kirilye]

Sounds fine to me in both languages.

[squaredomino]

It could mean a hotplate in a restaurant kitchen.

[BiancaPellet]

I took "a roast" to be short for "a roast dinner". Commonly used in British English to mean any form of meal where a roasted meat (e.g. duck, beef, pork...) is the centrepiece. So no problems here with that term and am interested/happy to see that it's also used in Italian :)