A sweet girl from Greece (7)
I believe the answer is:
granita
'a sweet' is the definition.
I don't know anything about this answer so I can't judge whether it can be defined by this definition.
'girl from greece' is the wordplay.
I cannot really see how this works, but
'girl' could be 'anita' and 'anita' is found in the answer.
'greece' could be 'gr' (abbreviation) and 'gr' is found within the answer.
This accounts for all the letters.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for granita that I've seen before include "final course perhaps" , "cold drink" , "Italian water ice" , "cold dessert" , "Kind of water ice - a rag tin (anag)" .)