Pouch closed, filled with noodle soup: capital! (10)
I believe the answer is:
sacramento
'capital' is the definition.
(state capital of California)
'pouch closed filled with noodle soup' is the wordplay.
'pouch' becomes 'sac' (synonyms).
'closed' becomes 'to' (as in a door closed to).
'filled with' is an insertion indicator.
'noodle soup' becomes 'ramen' (I've seen this in another clue).
'sac'+'to'='sacto'
'sacto' going around 'ramen' is 'SACRAMENTO'.
(Other definitions for sacramento that I've seen before include "State capital of California" , "US city" , "port" .)