Artist put in much energy creating hotchpotch (7)
I believe the answer is:
farrago
'hotchpotch' is the definition.
('farrago' can be a synonym of 'hotchpotch')
'artist put in much energy' is the wordplay.
'artist' becomes 'ra' (Royal Academician, member of Royal Academy of Arts).
'put in' means one lot of letters goes inside another.
'much' becomes 'far' (I've seen this in other clues).
'energy' becomes 'go' (I've seen this in other clues**).
'far'+'go'='fargo'
'ra' inserted within 'fargo' is 'FARRAGO'.
'creating' acts as a link.
(Other definitions for farrago that I've seen before include "Hash" , "A hotchpotch, perhaps of nonsense" , "Confused mass" , "confused situation" , "Confusion" .)