Gourmet mixed up rice with last of sauce (7)
I believe the answer is:
epicure
'gourmet' is the definition.
('epicure' can be a synonym of 'gourmet')
'mixed up rice with last of sauce' is the wordplay.
'mixed' is an anagram indicator.
'with' says to put letters next to each other.
'last of' suggests the final letters.
The final letter of 'sauce' is 'e'.
'up'+'rice'='uprice'
'uprice' with letters rearranged gives 'epicur'.
'epicur'+'e'='EPICURE'
(Other definitions for epicure that I've seen before include "Lover of fine food and drink" , "One enjoying good food and drink" , "Gourmet" , "anything but a John the Baptist type?" , "Person with fastidious tase in food and wine" .)