Perhaps Vietnamese food at the back (3,7)
I believe the answer is:
far eastern
'perhaps vietnamese' is the definition.
The definition suggests a singular noun which matches the answer.
'food at the back' is the wordplay.
'food' becomes 'fare' (fare is a kind of food).
'at the back' becomes 'astern' (I've seen this before).
'fare'+'astern'='FAR EASTERN'
Can you help me to learn more?
(Other definitions for far eastern that I've seen before include "from the Orient" , "Chinese?" , "from Japan, say?" , "Perhaps Japanese" .)