Excellent tart cooked with fries (5-4)
I believe the answer is:
first-rate
'excellent' is the definition.
(I've seen this before)
'tart cooked with fries' is the wordplay.
'cooked with' indicates an anagram (letters cooked into a new form).
'tart' with its letters anagrammed with 'fries' makes 'FIRST-RATE'.
(Other definitions for first-rate that I've seen before include "Prime" , "Top-class, excellent" , "Stir after to be really excellent" , "Start fire to be really excellent" , "Top-notch, excellent" .)