Sent back uncooked food, creating conflict (7)
I believe the answer is:
warfare
'conflict' is the definition.
(thesaurus)
'sent back uncooked food' is the wordplay.
'sent back' shows that the letters should be reversed in order.
'uncooked' becomes 'raw' ('raw' can be similar in meaning to 'uncooked').
'food' becomes 'fare' (fare is a kind of food).
'raw' reversed gives 'war'.
'war'+'fare'='WARFARE'
'creating' is the link.
(Other definitions for warfare that I've seen before include "Scraps, too, by the look of it" , "Strife" , "All-out fighting" , "Struggle" , "Armed conflict" .)