Simple citrus concoction (6)

I believe the answer is:

rustic

'simple' is the definition.
(I've seen this before)

'citrus concoction' is the wordplay.
'concoction' is an anagram indicator.
'citrus' is an anagram of 'RUSTIC'.

(Other definitions for rustic that I've seen before include "unrefined" , "Characteristic of rural life" , "Quaintly countrified" , "Countryman or countrified" , "Characteristic of country life" .)

I've seen this clue in The Independent.

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