Repasts turned out to be most lean (7)

I believe the answer is:

sparest

'most lean' is the definition.
('spare' can be similar in meaning to 'lean')

'repasts turned out' is the wordplay.
'turned out' indicates anagramming the letters (turn out can mean to organise).
'repasts' is an anagram of 'SPAREST'.

'to be' acts as a link.

I've seen this clue in The Daily Express.

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