Nice area street map's showing in red, with nothing cut out (4,5)
I believe the answer is:
cote dazur
'nice area' is the definition.
(I've seen this before)
'street map's showing in red with nothing cut out' is the wordplay.
'street map' becomes 'az' (an 'A to Z' is a street map).
'showing in' is an insertion indicator.
'with nothing' becomes 'o' (I've seen this in other clues).
'out' indicates anagramming the letters (out can mean wrong or inaccurate).
'red'+'o'+'cut'='redocut'
'redocut' with letters rearranged gives 'cotedur'.
'az' placed into 'cotedur' is 'COTE DAZUR'.
(Other definitions for cote dazur that I've seen before include "Nice area" , "French Med coast" , "French Riviera region" , "strand of French" , "French Riviera (4,1'4)" .)