Corporation boring well in France supplies tar product (7)
I believe the answer is:
bitumen
'tar product' is the definition.
'bitumen' can be an answer for 'tar' (I've seen this before). I am not certain of the 'product' bit.
'corporation boring well in france' is the wordplay.
'corporation' becomes 'tum' ('corporation' can humorously mean belly fat).
'boring' indicates putting letters inside (some letters must 'bore' a hole into other letters).
'well in france' becomes 'bien' (French for 'well').
'tum' put inside 'bien' is 'BITUMEN'.
'supplies' acts as a link.
Can you help me to learn more?
(Other definitions for bitumen that I've seen before include "Substance for surfacing roads" , "Mixed-up tar" , "might be used to 16 [RESURFACE]" , "Tarry substance used to surface roads and roofs" , "coverage on the streets?" .)