Also, I discern piercing flavour (7)
I believe the answer is:
aniseed
'flavour' is the definition.
(I've seen this before)
'also i discern piercing' is the wordplay.
'also' becomes 'and' (both can mean in addition).
'discern' becomes 'see' (I've seen this before).
'piercing' is an insertion indicator (some letters pierce a hole in others).
'i'+'see'='isee'
'and' placed around 'isee' is 'ANISEED'.
(Other definitions for aniseed that I've seen before include "Eased in (anag)" , "Pernod flavouring" , "Liquorice flavouring -- ie Danes (anag)" , "Strong herbal flavouring" , "Cake flavouring" .)