No new one working for an ingredient (5)
I believe the answer is:
onion
'an ingredient' 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 an association between them that I don't see?
'no new one working' is the wordplay.
'no' becomes 'O' (resembles 0 - 'no' can mean 'zero').
'new' becomes 'n' (abbreviation as in New Testament NT).
'one' becomes 'i' (Roman numeral).
'working' becomes 'on' (on can mean working or activated).
'o'+'n'+'i'+'on'='ONION'
'for' is the link.
Can you help me to learn more?
(Other definitions for onion that I've seen before include "Pungent vegetable" , "Aromatic flavourful versatile vegetable" , "Edible tear-jerker" , "Pungent edible bulb of the lily family" , "associated with 26 [TRIPE] ?" .)