Found bliss? Hate to differ! (9)
I believe the answer is:
establish
'found' is the definition.
(found can mean to set up or establish)
'bliss? hate to differ' is the wordplay.
'to differ' is an anagram indicator.
'bliss'+'hate'='blisshate'
'blisshate' is an anagram of 'ESTABLISH'.
(Other definitions for establish that I've seen before include "Found - institute" , "form" , "Set up or settle firmly in place" , "Found - this sable (anag)" , "Found - his stable (anag)" .)