Indian food: second helping in US city (9)
I believe the answer is:
baltimore
'us city' is the definition.
(city in Maryland, USA)
'indian food second helping' is the wordplay.
'indian food' becomes 'balti' (type of curry).
'second helping' becomes 'more'.
'balti'+'more'='BALTIMORE'
'in' acts as a link.
(Other definitions for baltimore that I've seen before include "City north-east of Washington DC" , "City of north Maryland" , "Large city in Maryland" , "Largest city of Maryland, USA" , "US city" .)