First course more piquant after seconds (7)
I believe the answer is:
starter
'first course' is the definition.
(I've seen this before)
'more piquant after seconds' is the wordplay.
'more piquant' becomes 'tarter' (both can mean sharp tasting).
'after' is a charade indicator (letters next to each other).
'seconds' becomes 's'.
'tarter' put after 's' is 'STARTER'.
(Other definitions for starter that I've seen before include "First course for beginner" , "No substitute" , "First course of meal" , "One giving signal to begin race" , "Appetiser" .)