Heart as impressive, incomplete dish (9)
I believe the answer is:
epicentre
'heart' is the definition.
(I have seen 'Pure heart' mean 'epicentre' so perhaps 'heart' could also mean 'epicentre')
'impressive incomplete dish' is the wordplay.
'impressive' becomes 'epic' (epic can mean grand or impressive).
'incomplete' means to remove the last letter.
'dish' becomes 'entree' (I've seen this before).
'entree' with its last letter taken away is 'entre'.
'epic'+'entre'='EPICENTRE'
'as' is the link.
(Other definitions for epicentre that I've seen before include "Locator for an earthquake" , "Pure heart" , "Quaking heart" , "most shocking point" , "Earthquake's surface location" .)