Bit of stuff found in immorality? Grand! (10)
I believe the answer is:
smattering
'bit' is the definition.
(I've seen this before)
'stuff found in immorality? grand' is the wordplay.
'stuff' becomes 'matter' (I've seen this in other clues**).
'found in' is an insertion indicator.
'immorality?' becomes 'sin' (sin is a kind of immorality).
'grand' becomes 'g' ('G' can be a synonym of 'grand').
'matter' inserted into 'sin' is 'smatterin'.
'smatterin'+'g'='SMATTERING'
'of' is the link.
(Other definitions for smattering that I've seen before include "superficial knowledge" , "Tiny amount (of knowledge)" , "Hint" , "Taste" , "Little bit" .)