Secret of the salty nuts (8)
I believe the answer is:
stealthy
'secret' is the definition.
(I've seen this before)
'the salty nuts' is the wordplay.
'nuts' indicates anagramming the letters (nuts can mean crazy).
'the'+'salty'='thesalty'
'thesalty' with letters rearranged gives 'STEALTHY'.
'of' acts as a link.
(Other definitions for stealthy that I've seen before include "'Furtive, surreptitious (8)'" , "Secretive, silent" , "Done in a quiet or secretive way" , "Acting in furtive or covert manner" , "Underhand" .)