Small mouthful of food left by TV inspector (6)
I believe the answer is:
morsel
'small mouthful of food' is the definition.
(I've seen this before)
'left by tv inspector' is the wordplay.
'left' becomes 'l' (common abbreviation).
'by' is a charade indicator (letters next to each other).
'tv inspector' becomes 'morse' (I've seen this before).
'l' after 'morse' is 'MORSEL'.
(Other definitions for morsel that I've seen before include "(Tasty) bit" , "Titbit" , "a little food" , "Tasty little piece" , "A shred as of bread" .)