Curate's food, say, good (in parts) (3)
I believe the answer is:
egg
'curate's food' is the definition.
'egg' can be an answer for 'food' (egg is a kind of food). I am not sure about the 'curate's' bit.
'say good in parts' is the wordplay.
I cannot quite see how this works, but
'say' could be 'eg' (both can mean for example) and 'eg' is located in the answer.
'good' could be 'g' (abbreviation) and 'g' is found in the answer.
No letters remain.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for egg that I've seen before include "Laid item" , "On the face, it's embarrassing" , "Early stage of development" , "brick is a good one" , "Mine (slang)" .)