Style of curry (5)
(Other definitions for korma that I've seen before include "Mildly-spiced curry" , "Curry dish" , "Mild Indian curry" , "Indian dish" .)
I believe this clue is a double definition.
'style' is the first definition.
(I have seen 'Style of curry' mean 'balti' so perhaps 'style' could also mean 'balti')
'curry' is the second definition.
'of' is the link.
(Other definitions for balti that I've seen before include "Type of curry" , "Hot spicy dish" , "Asian food" , "Indian food style" , "Spicy Pakistani cuisine with food cooked in a karahi" .)