A new piece of advice regarding early part of meal (9)
I believe the answer is:
antipasto
'early part of meal' is the definition.
(early course of a meal)
'a new piece of advice regarding' is the wordplay.
'new' becomes 'n' (abbreviation as in New Testament NT).
'piece of advice' becomes 'tip' (a tip is a piece of advice).
'regarding' becomes 'as to' (I've seen this in another clue).
'a'+'n'+'tip'+'asto'='ANTIPASTO'
(Other definitions for antipasto that I've seen before include "course leader" , "Italian dish" , "garnish!" , "Italian hors d'oeuvres" , "Italian food" .)