Josh's partner in curry house interrupting posh bloke after complaints - this dish isn't Indian! (4,10)
I believe the answer is:
beef stroganoff
'this dish isn't indian' is the definition.
'josh's partner in curry house interrupting posh bloke after complaints' is the wordplay.
'josh's partner in curry house' becomes 'rogan' (rogan josh is a type of curry).
'interrupting' means one lot of letters goes inside another.
'posh bloke' becomes 'toff' (informal term for an upper class person).
'after' is a charade indicator (letters next to each other).
'complaints' becomes 'beefs' (beef can mean a personal disagreement).
'rogan' inserted into 'toff' is 'troganoff'.
'troganoff' after 'beefs' is 'BEEF STROGANOFF'.
(Other definitions for beef stroganoff that I've seen before include "Meat dish" , "Dish with sour cream sauce" .)