Heavenly slice - late concoction (9)
I believe the answer is:
celestial
'heavenly' is the definition.
(I know that heavenly can be written as celestial)
'slice late concoction' is the wordplay.
'concoction' is an anagram indicator.
'slice'+'late'='slicelate'
'slicelate' is an anagram of 'CELESTIAL'.
(Other definitions for celestial that I've seen before include "Relating to the heavens" , "Heavenly" .)