Piece belonging to collector is Ottoman dish (7)
I believe the answer is:
risotto
'piece' is the definition.
The definition and answer can be both things that one consumes for nourishment as well as being singular nouns.
Perhaps you can see a link between them that I don't see?
'belonging to collector is ottoman dish' is the wordplay.
'belonging to' indicates a hidden word (I've seen this in other clues).
'RISOTTO' is hidden within 'collector is ottoman dish'.
Can you help me to learn more?
(Other definitions for risotto that I've seen before include "It has roots in Italian rice-based dish" , "Perhaps Italian" , "food dish" , "You cook it in stock" , "Italian course" .)