Stern, unconventional artist (5)

I believe the answer is:

ernst

'artist' is the definition.
(max ernst)

'stern unconventional' is the wordplay.
'unconventional' indicates anagramming the letters.
'stern' with letters rearranged gives 'ERNST'.

(Other definitions for ernst that I've seen before include "Young partner" , "Surrealist; stern (anag.)" , "Max __; Dadaist" , "Max --, German painter" , "He painted" .)

I've seen this clue in The Independent.

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