Subtle differences detected in new blended sauce with hidden name (7)
I believe the answer is:
nuances
'subtle differences' is the definition.
(I've seen this before)
'new blended sauce with hidden name' is the wordplay.
'new' becomes 'n' (common abbreviation eg NT for New Testament).
'blended' indicates an anagram.
'with hidden' means one lot of letters goes inside another (inserted letters are hidden inside).
'name' becomes 'n' (common abbreviation e.g. on forms).
'sauce' with letters rearranged gives 'uaces'.
'uaces' going around 'n' is 'uances'.
'n'+'uances'='NUANCES'
'detected in' acts as a link.
(Other definitions for nuances that I've seen before include "Subtleties" , "Subtle differences" , "Suspicion of" , "'Subtle variations, in meaning perhaps (7)'" , "Subtle distinctions or variations" .)