Spanish snack served up with heartless, haughty indifference (6)
I believe the answer is:
apathy
'indifference' is the definition.
(I know that indifference can be written as apathy)
'spanish snack served up with heartless haughty' is the wordplay.
'spanish snack' becomes 'tapa' (I've seen this before).
'served up' is a reversal indicator (in a down clue, letters go up).
'with' says to put letters next to each other.
'heartless' says to hollow out the word (remove centre letters).
'haughty' with its centre taken out is 'hy'.
'tapa' written backwards gives 'apat'.
'apat'+'hy'='APATHY'
(Other definitions for apathy that I've seen before include "State of listlessness or disinterest" , "Lack of interest or concern" , "Lack of interest in things in general" , "Impassivity - lack of feeling" , "Lack of emotion and interest" .)