Cheese might be said to produce this (10)
I believe the answer is:
photograph
'cheese' is the definition.
The definition and answer can be both to do with fundamental existence as well as being verbs in their base form.
Perhaps you can see a link between them that I can't see?
'said to produce this' is the wordplay.
I cannot quite understand how this works, but
'to' is within the answer.
This may be the basis of the clue (or it may be nonsense).
'might be' acts as a link.
(Other definitions for photograph that I've seen before include "Snapshot" , "Picture" .)