A bit of bread or cheese ingredient brought up (6)
I believe the answer is:
tenner
'a bit of bread' is the definition.
(ten pound note - bread can mean money)
'cheese ingredient brought up' is the wordplay.
'cheese ingredient' becomes 'rennet' (curdled milk used in cheese).
'brought up' says the letters should be written backwards (in a down clue, letters go up).
'rennet' reversed gives 'TENNER'.
'or' is the link.
(Other definitions for tenner that I've seen before include "UK banknote" , "Bank note" , "note form" , "A spot of money" , "Note - sounds like singer" .)