Lead with buffet covered in fruit (8)
I believe the answer is:
graphite
'lead' is the definition.
(I've seen this before)
'with buffet covered in fruit' is the wordplay.
'with' is an insertion indicator.
'buffet' becomes 'hit' (buffet can mean to beat or pound).
'covered in fruit' becomes 'grape' (I can't explain this - if you can you should give a lot more credence to this answer).
'hit' put within 'grape' is 'GRAPHITE'.
Can you help me to learn more?
(Other definitions for graphite that I've seen before include "Writing material" , "black stuff" , "Form of carbon used in pencil leads" , "Black carbon used in lead pencils" , "Pig hater (anag)" .)