Thai apricot and chop recipe, doctors swear by it (11,4)
I believe the answer is:
hippocratic oath
'doctors swear by it' is the definition.
(I've seen this in another clue)
'thai apricot and chop recipe' is the wordplay.
'and' says to put letters next to each other.
'recipe' is an anagram indicator.
'thai'+'apricot'='thaiapricot'
'thaiapricot' put after 'chop' is 'chopthaiapricot'.
'chopthaiapricot' with letters rearranged gives 'HIPPOCRATIC OATH'.
(Other definitions for hippocratic oath that I've seen before include "Doctor takes" , "well-known pledge" .)